How Do I Respond to a “Coming Out”?

In this episode, Dr. Betters answers the question, Donata asks "My granddaughter (age 13) believes she is gay and dresses that way. Her parents have condoned this. Her father, my son, was raised in a Christian home, and knows better, but allows this. There are other things going on in this family that is tearing my heart out with a heaviness for my granddaughter to not be left behind. Please help me in the way to approach her, that she is not left behind that Satan doesn't use it to pull her further away, but the Lord uses it to pull her closer to him, that she may become a witness for others in Jesus name."