In October 2021, New York state enacted sweeping changes to the Domestic Relations Law and the Family Court Act by becoming the 41st state to extend the age for which the primary custodial parent of a child can receive support from the non-custodial parent. That age has now been extended from 21 to 26 years.

For custodial parents with existing support orders, to extend the age, they must petition the court to modify the order of support by demonstrating that the child who is the subject of the support order has a developmental disability codified under New York State Mental Health Law §1.03, which renders the adult-age child "principally dependent" on the petitioning party. Under Mental Health Law §1.03, the disability must (1) have originated before the child became 22 years old; (2) have continued or can be expected to continue indefinitely; and (3) constitutes a substantial handicap to the child's ability to function normally in society.

The goal of the legislature in passing this law is to provide custodial parents who are charged with caring for an adult-age child with the ability to continue supporting their children, with continuing financial contribution from the non-custodial party. Under the previous law, when a child attained the age of 21 the payor's obligation for support was immediately terminated barring an agreement between the parties to extend the age of support. As a result of this new statute, a parent with a child, despite attaining age 21, who is unable to work or provide any meaningful level of financial support for themselves due to a developmental disability, is now able to petition the court to receive an order, or modify an existing order, of child support from the non-custodial party beyond age 21 or until the adult-age child attains 26 years of age.