Thanks to Dana Rudolph at Mombian to pointing out to me that Cynthia Nixon thinks her upcoming marriage to Christine Marinoni will give Christine a legal right to a relationship with the children Cynthia had with Danny Mozes. After Ellen reported that at a rally last Sunday in New York, Nixon announced her engagement to Marinoni and called for the right to marry in New York, noting that Marinoni is a stay-at-home mom but currently has no legal right to the children if Nixon dies.
It sounds to me like Nixon is under the impression that Marinoni will have such legal rights after they marry, but this isn't true. Marinoni will become a stepparent, but in New York -- and many places (maybe most) -- stepparents don't have rights to custody or visitation. If Nixon dies, the children would go to their father, and he would decide how much time, if any, Marinoni could spend with the children.
Advocates in NY have been trying for years to overturn a terrible 1991 court decision defining "parent" so narrowly that a biological mom could totally block access between her former partner and her biological child, even though the former partner had totally functioned as a parent to the child with the bio mom's consent. That opinion was later used to justify denying a stepfather access to his stepchildren. (Thanks to New York lawyer Michele Kahn for confirming this for me.) But even if that case is overruled, the principle involved concerns two co-parents, not a child who has two parents and then gains another parental figure -- stepparent or otherwise.
If Nixon's children did not have another parent, Marinoni could adopt them, and she could do that regardless of whether she and Nixon married. She could also adopt them if Mozes agreed to terminate his parental rights, but that's not the situation here. Again, Nixon and Marinoni would not have to be married.
Marriage and legal parenthood are two distinct things. If Cynthia Nixon is confused about this, I bet lots of folks are.