N.Y. Gen. Oblig. Law § 5-1551

§ 5-1551. Power of parent to designate a person in parental relation.\nA parent of a minor or incapacitated person may designate another person\nas a person in parental relation to such minor or incapacitated person\npursuant to sections twenty-one hundred sixty-four and twenty-five\nhundred four of the public health law and sections two and thirty-two\nhundred twelve of the education law for a period not exceeding twelve\nmonths provided that there is no prior order of any court in any\njurisdiction currently in effect that would prohibit such parent from\nhimself or herself exercising the same or similar authority, and\nprovided further, that, in the case where a court has ordered that both\nparents must agree on education or health decisions regarding the child,\na designation pursuant to this subdivision shall not be valid unless\nboth parents have consented thereto. Such designation shall be in the\nform prescribed by section 5-1552 of this title, and may be presented to\nany school, health care provider or health plan that requires such\ndesignation by either the parent or the designee.\n