My boyfriends daughter in 11 years old and wants to live with her father and I, her mom has full custidy. At what age does she have the right to say who she wants to live with in Indiana?

She has a right to speak her mind at any age. But as far as in court then its not a consideration. Children that age can be manipulated too easy. SO even if the courts hear it they don't have to consider it when making their decision.

She can move where she wants at 18, the age a court at a motion hearing will listen to a child varies ( even by local court rules) but 11 or 12 is when courts often allow a child to testify

This is a frequently asked question. A child can never choose. The decision on custody is made by a judge. Some states allow more weight to be put on the child's preference as they get older, but its still up to the judge.

At 11 there is almost no chance of a judge allowing a change in custody.