Section 101 - Liability of relatives to support1. Except as otherwise provided by law, the spouse or parent of a recipient of public assistance or care or of a person liable to become in need thereof shall, if of sufficient ability, be responsible for the support of such person, provided that a parent shall be responsible only for the support of a child under the age of twenty-one years. Step-parents shall in like manner be responsible for the support of step-children under the age of twenty-one years. Nothing herein shall impose any liability upon a person to support the adopted child of his or her spouse if such child was adopted after the adopting spouse is living separate and apart from the non-adopting spouse pursuant to a legally recognizable separation agreement or decree under the domestic relations law. Such liability shall not be imposed for so long as the spouses remain separate and apart after the adoption.2. The liability imposed by this section shall be for the benefit of the public welfare district concerned or any legally incorporated non-profit institution which receives payments from any governmental agency for the care of medically indigent persons, and such liability may be enforced by appropriate proceedings and actions in a court of competent jurisdiction. Such proceedings and actions may be brought by such an institution in any court wherein a similar proceeding or action could be brought by a public welfare official.3. The expiration of any period of time for the payment of maintenance by a court in a matrimonial action shall not be a bar to the enforcement of the liability imposed by this section.N.Y. Soc. Serv. Law § 101