Exhibit 3.236

TYLER REHABILITATION HOSPITAL, INC.

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BY-LAWS

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ARTICLE I

OFFICES

Section 1. The registered office shall be located in Dallas, Texas.

Section 2. The corporation may also have offices at such other places both within and without the State of Texas as the board of directors may from time to time determine or the business of the corporation may require.

ARTICLE II

ANNUAL MEETINGS OF SHAREHOLDERS

Section 1. All meetings of shareholders for the election of directors shall be held in Mechanicsburg, State of Pennsylvania, at such place as may be fixed from time to time by the board of directors. Said meetings may also be held at such other place either within or without the State of Texas as shall be designated from time to time by the board of directors and stated in the notice of the meeting.

Section 2. Annual meetings of shareholders, commencing with the year 1992, shall be determined by the Board of Directors, and transact such other business as may properly be brought before the meeting.

Section 3. Written or printed notice of the annual meeting stating the place, day and hour of the meeting shall be delivered not less than ten nor more than fifty days before the date of the meeting, either personally or by mail, by or at the direction of the president, the secretary, or the officer or persons calling the meeting, to each shareholder of record entitled to vote at such meeting.

ARTICLE III

SPECIAL MEETINGS OF SHAREHOLDERS

Section 1. Special meetings of shareholders for any purpose other than the election of directors may be held at such time and place within or without the State of Texas as shall be stated in the notice of the meeting or in a duly executed waiver of notice thereof.

Section 2. Special meetings of the shareholders, for any purpose or purposes, unless otherwise prescribed by statute or by the articles of incorporation, may be called by the president, the board of directors, or the holders of not less than one-tenth of all the shares entitled to vote at the meeting.

Section 3. Written or printed notice of a special meeting stating the place, day and hour of the meeting and the purpose or purposes for which the meeting is called, shall be delivered not less than ten nor more than fifty days before the date of the meeting, either personally or by mail, by or at the direction of the president, the secretary, or the officer or persons calling the meeting, to each shareholder of record entitled to vote at such meeting.

Section 4. The business transacted at any special meeting of shareholders shall be limited to the purposes stated in the notice.

ARTICLE IV

QUORUM AND VOTING OF STOCK

Section 1. The holders of a majority of the shares of stock issued and outstanding and entitled to vote, represented in person or by proxy, shall constitute a quorum at all meetings of the shareholders for the transaction of business except as otherwise provided by

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statute or by the articles of incorporation. If, however, such quorum shall not be present or represented at any meeting of the shareholders, the shareholders present in person or represented by proxy shall have power to adjourn the meeting from time to time, without notice other than announcement at the meeting, until a quorum shall be present or represented. At such adjourned meeting at which a quorum shall be present or represented any business may be transacted which might have been transacted at the meeting as originally notified.

Section 2. If a quorum is present, the affirmative vote of a majority of the shares of stock represented at the meeting shall be the act of the shareholders unless the vote of a greater number of shares of stock is required by law or the articles of incorporation.

Section 3. Each outstanding share of stock, having voting power, shall be entitled to one vote on each matter submitted to a vote at a meeting of shareholders. A shareholder may vote either in person or by proxy executed in writing by the shareholder or by his duly authorized attorney-in-fact.

In all elections for directors every shareholder, entitled to vote, shall have the right to vote, in person or by proxy, the number of shares of stock owned by him, for as many persons as there are directors to be elected, or to cumulate the vote of said shares, and give one candidate as many votes as the number of directors multiplied by the number of his shares of stock shall equal, or to distribute the votes on the same principle among as many candidates as he may see fit.

Section 4. Any action required to be taken at a meeting of the shareholders may be taken without a meeting if a consent in writing, setting forth the action so taken, shall be signed by all of the shareholders entitled to vote with respect to the subject matter thereof.

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ARTICLE V

DIRECTORS

Section 1. The number of directors shall be One (1). Directors need not be residents of the State of Texas nor shareholders of the corporation. The directors, other than the first board of directors, shall be elected at the annual meeting of the shareholders, and each director elected shall serve until the next succeeding annual meeting and until his successor shall have been elected and qualified. The first board of directors shall hold office until the first annual meeting of shareholders.

Section 2. Any vacancy occurring in the board of directors may be filled by the shareholders at an annual or a special meeting or by the affirmative vote of a majority of the remaining directors though less than a quorum of the board of directors. A director elected to fill a vacancy shall be elected for the unexpired portion of the term of his predecessor in office.

Any directorship to be filled by reason of an increase in the number of directors may be filled by election at an annual meeting or at a special meeting of shareholders called for that purpose. A director elected to fill a newly created directorship shall serve until the next succeeding annual meeting of shareholders and until his successor shall have been elected and qualified. Any directorship to be filled by reason of an increase in the number of directors may also be filled by the board of directors for a term of office until the next election of directors by shareholders; provided no more than two directorships may be so filled during a period between any two successive annual meetings of shareholders.

Whenever the holders of any class or series of shares are entitled to elect one or more directors by the provisions of the articles of incorporation, any vacancies in such directorships and any newly created directorships of such class or series to be filled by reason of

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an increase in the number of such directors may be filled by the affirmative vote of a majority of the directors elected by such class or series then in office or by a sole remaining director so elected, or by the vote of the holders of the outstanding shares of such class or series, and such directorships shall not in any case be filled by the vote of the remaining directors or the holders of the outstanding shares as a whole unless otherwise provided in the articles of incorporation.

Section 3. The business affairs of the corporation shall be managed by its board of directors which may exercise all such powers of the corporation and do all such lawful acts and things as are not by statute or by the articles of incorporation or by these by-laws directed or required to be exercised or done by the shareholders.

Section 4. The directors may keep the books of the corporation, except such as are required by law to be kept within the state, outside of the State of Texas, at such place or places as they may from time to time determine.

Section 5. The board of directors, by the affirmative vote of a majority of the directors then in office, and irrespective of any personal interest of any of its members, shall have authority to establish reasonable compensation of all directors for services to the corporation as directors, officers or otherwise.

ARTICLE VI

MEETINGS OF THE BOARD OF DIRECTORS

Section 1. Meetings of the board of directors, regular or special, may be held either within or without the State of Texas.

Section 2. The first meeting of each newly elected board of directors shall be held at such time and place as shall be fixed by the vote of the shareholders at the annual meeting and no notice of such meeting shall be necessary to the newly elected directors in order legally to constitute the meeting, provided a quorum shall be present, or it may convene at such place and time as shall be fixed by the consent in writing of all the directors.

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Section 3. Regular meetings of the board of directors may be held upon such notice, or without notice, and at such time and at such place as shall from time to time be determined by the board.

Section 4. Special meetings of the board of directors may be called by the president on One (1) days’ notice to each director, either personally or by mail or by telegram; special meetings shall be called by the president or secretary in like manner and on like notice on the written request of two directors.

Section 5. Attendance of a director at any meeting shall constitute a waiver of notice of such meeting, except where a director attends for the express purpose of objecting to the transaction of any business because the meeting is not lawfully called or convened. Neither the business to be transacted at, nor the purpose of, any regular or special meeting of the board of directors need be specified in the notice or waiver of notice of such meeting.

Section 6. A majority of the directors shall constitute a quorum for the transaction of business unless a greater number is required by law or by the articles of incorporation. The act of a majority of the directors present at any meeting at which a quorum is present shall be the act of the board of directors, unless the act of a greater number is required by statute or by the articles of incorporation. If a quorum shall not be present at any meeting of directors, the directors present thereat may adjourn the meeting from time to time, without notice other than announcement at the meeting, until a quorum shall be present.

Section 7. Unless otherwise restricted by the articles of incorporation or these by-laws, any action required or permitted to be taken at any meeting of the board of directors or

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of any committee thereof may be taken without a meeting, if all members of the board or committee, as the case may be, consent thereto in writing which shall set forth the action taken and be signed by all members of the board of directors or of the committee as the case may be.

ARTICLE VII

COMMITTEES OF DIRECTORS

Section 1. The board of directors, by resolution adopted by a majority of the full board of directors, may designate from among its members an executive committee and one or more other committees, each of which shall be comprised of one or more members and, to the extent provided in the resolution, shall have and may exercise all of the authority of the board of directors, except that no such committee shall have the authority of the board of directors in reference to amending the articles of incorporation, approving a plan of merger or consolidation, recommending to the shareholders the sale, lease, or exchange of all or substantially all of the property and assets of the corporation otherwise than in the usual and regular course of its business, recommending to the shareholders a voluntary dissolution of the corporation or a revocation thereof, amending, altering, or repealing the bylaws of the corporation or adopting new bylaws for the corporation, filling vacancies in the board of directors or any committee, filling any directorship to be filled by reason of an increase in the number of directors, electing or removing officers or members of any committee, fixing the compensation of any member of a committee, or altering or repealing any resolution of the board of directors which by its terms provides that it shall not be so amendable or repealable; and, unless the resolution expressly so provides, no committee shall have the power or authority to declare a dividend or to authorize the issuance of shares of the corporation.

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ARTICLE VIII

NOTICES

Section 1. Whenever, under the provisions of the statutes or of the articles of incorporation or of these by-laws, notice is required to be given to any director or shareholder, it shall not be construed to mean personal notice, but such notice may be given in writing, by mail, addressed to such director or shareholder, at his address as it appears on the records of the corporation, with postage thereon prepaid, and such notice shall be deemed to be given at the time when the same shall be deposited in the United States mail. Notice to directors may also be given by telegram.

Section 2. Whenever any notice whatever is required to be given under the provisions of the statutes or under the provisions of the articles of incorporation or these by-laws, a waiver thereof in writing signed by the person or persons entitled to such notice, whether before or after the time stated therein, shall be deemed equivalent to the giving of such notice.

ARTICLE IX

OFFICERS

Section 1. The officers of the corporation shall be chosen by the board of directors and shall be a president and a secretary. The board of directors may also elect or appoint such other officers, including assistant officers and agents as may be deemed necessary.

Section 2. The board of directors at its first meeting after each annual meeting of shareholders shall choose a president and a secretary neither of whom need be a member of the board.

Section 3. The board of directors may also appoint such other officers and agents as it shall deem necessary who shall hold their offices for such terms and shall exercise such powers and perform such duties as shall be determined from time to time by the board of directors.

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Section 4. The salaries of all officers and agents of the corporation shall be fixed by the board of directors.

Section 5. The officers of the corporation shall hold office until their successors are chosen and qualify. Any officer elected or appointed by the board of directors may be removed at any time by the affirmative vote of a majority of the board of directors. Any vacancy occurring in any office of the corporation shall be filled by the board of directors.

THE PRESIDENT

Section 6. The president shall be the chief executive officer of the corporation, shall preside at all meetings of the shareholders and the board of directors, shall have general and active management of the business of the corporation and shall see that all orders and resolutions of the board of directors are carried into effect.

Section 7. He shall execute bonds, mortgages and other contracts requiring a seal, under the seal of the corporation, except where required or permitted by law to be otherwise signed and executed and except where the signing and execution thereof shall be expressly delegated by the board of directors to some other officer or agent of the corporation.

THE VICE-PRESIDENTS

Section 8. The vice-president, if there is one, or if there shall be more than one, the vice-presidents in the order determined by the board of directors, shall, in the absence or disability of the president, perform the duties and exercise the powers of the president and shall perform such other duties and have such other powers as the board of directors may from time to time prescribe.

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THE SECRETARY AND ASSISTANT SECRETARIES

Section 9. The secretary shall attend all meetings of the board of directors and all meetings of the shareholders and record all the proceedings of the meetings of the corporation and of the board of directors in a book to be kept for that purpose and shall perform like duties for the standing committees when required. He shall give, or cause to be given, notice of all meetings of the shareholders and special meetings of the board of directors, and shall perform such other duties as may be prescribed by the board of directors or president, under whose supervision he shall be. He shall have custody of the corporate seal of the corporation and he, or an assistant secretary, shall have authority to affix the same to any instrument requiring it and when so affixed, it may be attested by his signature or by the signature of such assistant secretary. The board of directors may give general authority to any other officer to affix the seal of the corporation and to attest the affixing by his signature.

Section 10. The assistant secretary, if there is one, or if there be more than one, the assistant secretaries in the order determined by the board of directors, shall, in the absence or disability of the secretary, perform the duties and exercise the powers of the secretary and shall perform such other duties and have such other powers as the board of directors may from time to time prescribe.

THE TREASURER AND ASSISTANT TREASURERS

Section 11. The treasurer, if there is one, shall have the custody of the corporate funds and securities and shall keep full and accurate accounts of receipts and disbursements in books belonging to the corporation and shall deposit all moneys and other valuable effects in the name and to the credit of the corporation in such depositories as may be designated by the board of directors.

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Section 12. He shall disburse the funds of the corporation as may be ordered by the board of directors, taking proper vouchers for such disbursements, and shall render to the president and the board of directors, at its regular meetings, or when the board of directors so requires, an account of all his transactions as treasurer and of the financial condition of the corporation.

Section 13. If required by the board of directors, he shall give the corporation a bond in such sum and with such surety or sureties as shall be satisfactory to the board of directors for the faithful performance of the duties of his office and for the restoration to the corporation, in case of his death, resignation, retirement or removal from office, of all books, papers, vouchers, money and other property of whatever kind in his possession or under his control belonging to the corporation.

Section 14. The assistant treasurer, if there is one, or, if there shall be more than one, the assistant treasurers in the order determined by the board of directors, shall, in the absence or disability of the treasurer, perform the duties and exercise the powers of the treasurer and shall perform such other duties and have such other powers as the board of directors may from time to time prescribe.

ARTICLE X

CERTIFICATES FOR SHARES

Section 1. The shares of the corporation shall be represented by certificates signed by the president and secretary or such other officers as may be elected or appointed, and may be sealed with the seal of the corporation or a facsimile thereof.

When the corporation is authorized to issue shares of more than one class there shall be set forth upon the face or back of the certificate, or the certificate shall have a statement

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that the corporation will furnish to any shareholder upon request and without charge, a full statement of the designations, preferences, limitations and relative rights of the shares of each class authorized to be issued and, if the corporation is authorized to issue any preferred or special class in series, the variations in the relative rights and preferences between the shares of each such series so far as the same have been fixed and determined and the authority of the board of directors to fix and determine the relative rights and preferences of subsequent series. When the corporation is authorized to issue shares of more than one class, every certificate shall also set forth upon the face or the back of such certificate a statement that there is set forth in the articles of incorporation on file in the office of the Secretary of State a full statement of all the designations, preferences, limitations and relative rights, including voting rights, of the shares of each class authorized to be issued and the corporation will furnish a copy of such statement to the record holder of the certificate without charge on written request to the corporation at its principal place of business or registered office. Every certificate shall have noted thereon any information required to be set forth by the Texas Business Corporation Act and such information shall be set forth in the manner provided in said Act.

Section 2. The signatures of the officers of the corporation upon a certificate may be facsimiles if the certificate is countersigned by a transfer agent, or registered by a registrar, other than the corporation itself or an employee of the corporation. In case any officer who has signed or whose facsimile signature has been placed upon such certificate shall have ceased to be such officer before such certificate is issued, it may be issued by the corporation with the same effect as if he were such officer at the date of its issue.

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LOST CERTIFICATES

Section 3. The board of directors may direct a new certificate to be issued in place of any certificate theretofore issued by the corporation alleged to have been lost or destroyed. When authorizing such issue of a new certificate, the board of directors, in its discretion and as a condition precedent to the issuance thereof, may prescribe such terms and conditions as it deems expedient, and may require such indemnities as it deems adequate, to protect the corporation from any claim that may be made against it with respect to any such certificate alleged to have been lost or destroyed.

TRANSFERS OF SHARES

Section 4. Upon surrender to the corporation or the transfer agent of the corporation of a certificate representing shares duly endorsed or accompanied by proper evidence of succession, assignment or authority to transfer, a new certificate shall be issued to the person entitled thereto, and the old certificate cancelled and the transaction recorded upon the books of the corporation.

CLOSING OF TRANSFER BOOKS

Section 5. For the purpose of determining shareholders entitled to notice of or to vote at any meeting of shareholders, or any adjournment thereof or entitled to receive payment of any dividend, or in order to make a determination of shareholders for any other proper purpose, the board of directors may provide that the stock transfer books shall be closed for a stated period but not to exceed, in any case, fifty days. If the stock transfer books shall be closed for the purpose of determining shareholders entitled to notice of or to vote at a meeting of shareholders, such books shall be closed for at least ten days immediately preceding such meeting. In lieu of closing the stock transfer books, the board of directors may fix in advance a date as the record date for any such determination of shareholders, such date in any case to be

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not more than fifty days and, in case of a meeting of shareholders, not less than ten days prior to the date on which the particular action, requiring such determination of shareholders, is to be taken. If the stock transfer books are not closed and no record date is fixed for the determination of shareholders entitled to notice of or to vote at a meeting of shareholders, or shareholders entitled to receive payment of a dividend, the date on which notice of the meeting is mailed or the date on which the resolution of the board of directors declaring such dividend is adopted, as the case may be, shall be the record date for such determination of shareholders. When a determination of shareholders entitled to vote at any meeting of shareholders has been made as provided in this section, such determination shall apply to any adjournment thereof.

REGISTERED SHAREHOLDERS

Section 6. The corporation shall be entitled to recognize the exclusive right of a person registered on its books as the owner of shares to receive dividends, and to vote as such owner, and to hold liable for calls and assessments a person registered on its books as the owner of shares, and shall not be bound to recognize any equitable or other claim to or interest in such share or shares on the part of any other person, whether or not it shall have express or other notice thereof, except as otherwise provided by the laws of Texas.

LIST OF SHAREHOLDERS

Section 7. The officer or agent having charge of the transfer books for shares shall make, at least ten days before each meeting of shareholders, a complete list of the shareholders entitled to vote at such meeting, arranged in alphabetical order, with the address of each and the number of shares held by each, which list, for a period of ten days prior to such meeting, shall be kept on file at the registered office of the corporation and shall be subject to inspection by any shareholder at any time during usual business hours. Such list shall also be

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produced and kept open at the time and place of the meeting and shall be subject to the inspection of any shareholder during the whole time of the meeting. The original share ledger or transfer book, or a duplicate thereof, shall be prima facie evidence as to who are the shareholders entitled to examine such list or share ledger or transfer book or to vote at any meeting of the shareholders.

ARTICLE XI

GENERAL PROVISIONS

DIVIDENDS

Section 1. Subject to the provisions of the articles of incorporation relating thereto, if any, dividends may be declared by the board of directors at any regular or special meeting, pursuant to law. Dividends may be paid in cash, in property or in shares of the capital stock, subject to any provisions of the articles of incorporation.

Section 2. Before payment of any dividend, there may be set aside out of any funds of the corporation available for dividends such sum or sums as the directors from time to time, in their absolute discretion, think proper as a reserve fund to meet contingencies, or for equalizing dividends, or for repairing or maintaining any property of the corporation, or for such other purpose as the directors shall think conducive to the interest of the corporation, and the directors may modify or abolish any such reserve in the manner in which it was created.

CHECKS

Section 3. All checks or demands for money and notes of the corporation shall be signed by such officer or officers or such other person or persons as the board of directors may from time to time delegate.

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FISCAL YEAR

Section 4. The fiscal year of the corporation shall be fixed by resolution of the board of directors.

SEAL

Section 5. The corporate seal shall have inscribed thereon the name of the corporation, the year of its organization and the words “Corporate Seal, Texas”. The seal may be used by causing it or a facsimile thereof to be impressed or affixed or in any manner reproduced.

ARTICLE XII

AMENDMENTS

Section 1. These by-laws may be altered, amended, or repealed or new by-laws may be adopted by the affirmative vote of a majority of the board of directors at any regular or special meeting of the board subject to repeal or change at any regular or special meeting of shareholders at which a quorum is present or represented, by the affirmative vote of a majority of the stock entitled to vote, provided notice of the proposed repeal or change be contained in the notice of such meeting.

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