On and after June 9, 1972, except as otherwise specifically provided in this code, no person who is eighteen years of age or older shall lack legal capacity, by reason of his age, to enter into contracts, sell or purchase real or personal property, create a lien, execute any legal or other written instrument, prosecute or defend legal actions, assert claims or deal in his own affairs in any manner whatsoever.

The provisions of this section, and the provisions of chapter sixty-one, acts of the Legislature, regular session, 1972, reducing various prescribed age requirements to eighteen years of age, shall not, however, by operation of law affect any rights, duties, obligations or interests accruing or vesting by virtue of any statute, act, event, transaction, order, judgment or decree prior to June 9, 1972, or any cause of action which arose or any civil action or claim instituted or asserted prior to such date, and any such right, duty, obligation, interest, cause of action, civil action or claim may be enforced, exercised, enjoyed, terminated, discharged, consummated, prosecuted, maintained or asserted with like effect as if said chapter sixty-one had not been enacted: Provided, That any person who has attained the age of eighteen years shall have full power and authority to exercise any and all of the rights, privileges and powers granted to him in the first paragraph of this section with respect to any legal or equitable interest acquired by or which vested in such person before he became eighteen years of age: Provided, however, That under no circumstances whatever shall any of the changes made by said chapter sixty-one have any effect upon any of the terms or provisions of or any conditions imposed by any last will and testament, trust agreement or any other written instrument of any kind or character executed prior to such date of June 9, 1972: Provided further, That any order or mandate providing for payment of child support for any person up to the age of twenty-one years contained in any decree or order of divorce or separate maintenance or in any order in any nonsupport or bastardy proceeding, which decree or order was entered prior to June 9, 1972, may by order of the court be terminated as to such person upon such person attaining the age of eighteen years. Moreover, the provisions of this section shall not affect any acts performed or transactions entered into by a person under the age of twenty-one years prior to June 9, 1972. No change in the general age of legal capacity or in the definitions of the words "under disability," "infant" or "minor" contained in section ten, article two of this chapter shall alter any statute of limitations as to causes of action arising before such date of June 9, 1972.