If you've helped raise a child, you can seek custody and visitation rights even if you aren't related by law or biology, the state's highest court rules.

New York State may pride itself on being in the forefront of progress on many social issues — it was an early adopter of marriage equality, for instance — but it’s just now catching up to most other states in expanding the definition of parenthood.

The New York State Court of Appeals, the state’s highest court, ruled Tuesday that “a caretaker who is not related to, or the adoptive guardian of, a child could still be permitted to ask for custody and visitation rights,” The New York Times reports.

The ruling, which involved a same-sex couple, is important to all types of families and brings New York in line with most of the states in the nation, including some very conservative ones, which allow these “de facto parents,” as the Times puts it, to seek custody and visitation rights.

The judges ruled in a dispute between women identified in court papers only as Brooke S.B. and Elizabeth A. C.C. They entered into a relationship in 2006 but did not marry, as New York did not allow same-sex marriages at the time, and they could not afford to travel to a state that did. Elizabeth became pregnant through alternative insemination in 2008 and gave birth to a son the following year.

“Though Brooke had no legal or biological ties to the child, a boy, she maintained a close relationship with him for years, cutting his umbilical cord at birth, giving him her last name and raising him jointly with Elizabeth,” the Times reports. The couple split up in 2010, but Brooke continued to be a parent to him, according to Lambda Legal, which was part of her legal team in the case. In 2013, Elizabeth cut Brooke off from contact with the boy, leading Brooke to sue for custody and visitation.

A family court dismissed her case, and an appellate court agreed, both saying they had to follow the precedent set by a 1991 Court of Appeals ruling in a case known as Alison D., which held that “nonbiological, nonmarried, nonadoptive parents are legal strangers to the children they raised with a same-sex partner,” Susan Sommer, Lambda Legal’s national director of constitutional litigation, explained in a press release.

But in ruling on the new case, the Court of Appeals recognized that the understandings of marriage and family have evolved since 1991. “The definition of ‘parent’ established by this court 25 years ago in Alison D. has become unworkable when applied to increasingly varied familial relationships,” Judge Sheila Abdus-Salaam wrote for the court majority.

She further noted, “Alison D.’s foundational premise of heterosexual parenting and nonrecognition of same-sex couples is unsustainable,” especially in light of the marriage equality law New York State passed in 2011 and the U.S. Supreme Court ruling last year that brought equal marriage rights to all 50 states.

“Where a partner shows by clear and convincing evidence that the parties agreed to conceive a child and to raise the child together, the nonbiological, nonadoptive partner has standing to seek visitation and custody,” Abdus-Salaam added.

“We are extremely gratified that Brooke will finally have her day in court to establish that she is the parent of the son she cherishes,” Sommer said. We are eager for them to be reunited as soon as possible.”

The ruling also applies in a similar case, Estrellita A. v. Jennifer L.D., which involved similar issues, Lambda Legal notes. In this case a lesbian nonbiological parent who was ordered to pay child support argued that she should be able to petition for custody and visitation rights.

The decision puts New York on the same page as many other states, even conservative ones like Oklahoma and South Carolina, the Times notes. “Many courts have simply said that this person looks like a parent and you cannot just eliminate them from the child’s life,” Nancy D. Polikoff, a professor at the American University Washington College of Law, told the paper. “To have New York, where there are so many same-sex couples, be an outlier was a problem. But this catches New York up.”