N.Y. Comp. Codes R. & Regs. tit. 18, § 422.1
(b) A child means a person who meets all of the following criteria:
(1) Age.
(ii) is between the ages of 18 and 21 years and entered foster care before his or her 18th birthday, and has consented to remain in foster care past his or her 18th birthday; and
(3) Placement.
For purposes of this Part: