Chelsea, who returned home last week after being missing for several days, decided to move in with her birth mother upon turning 18.
Mississippi is the last state with such a ban.
The landmark Supreme Court marriage equality ruling leads to a legal victory for same-sex parents in Utah.
The civil rights organization is hunting for a constitutional solution to the law that discriminates against LGBT couples.
If signed into law, faith-based adoption agencies in the state could refuse to allow LGBT people to adopt, or place foster children in homes headed by LGBT Michiganders.
U.S. Sen. Kirsten Gillibrand will introduce a bill to ban discrimination against LGBT people who seek to adopt children.
President Obama makes LGBT history again by advocating foster and adoptive parents be chosen without regard to sexual orientation or gender identity.
The repeal measure, which has already passed the House, received bipartisan approval in the Senate after emotional debate.