There is no such process. A child of 12 is not allowed to choose.
Depends if the parent has said that the child can choose what he wants, if the parent has then it is recommended that the child is given the choice of the school that they get to go to
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Yes, legally at the age of twelve a child can choose which parent he / or she wants to live with and visits with.
In Texas, if a child is 14 or older, he/she can choose to live with a grandparent as long as permission is given by the custodial parent.
no see links below
The court might ask what parent he wants to live with but they are in no way obligated to follow his wish and especially not if the parent were abusive.
In my state (Georgia) when a child is 14 and both parents are in a position to care for the child then the child can choose which parent he/she wants to live with. The judge will of course have the final say so, but the child's wishes are greatly considered.
depending on the age of the child, the courts may evaluate your situation in making a decision on which parent will maintain custodial status. If the parent to which you are interested in living with, your parent must also participate with the courts to make a final decision as to your residency and whom you reside with.
A minor can not choose where to live. That is up to the parents or the court depending on the details. If your non-custodial parent who lives out of state wants you to live with him/her, they have to petition for custody unless your custodial parent will consent to the change and join in a modification of the custody order.
no see links below
Here the child at 16 years can not decide where she or he wants to live. As they are minors the court will decide it for them.