Age 18
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Joint custody of a child can be decided by the parents whereby they share responsibilities for the child. Schedules can be worked out so the child spends time with both parents. Courts can also decide to award parents joint custody in the case of legal disputes and indeed some states have a preference for this in law.
The court will decide what's best for the child according to the laws of the jurisdiction and the facts of the situation. The courts does not allow a child to make such decisions.
Yessee link
No, you cannot move a child out of state if you have joint custody.
No, there is still a parent left with custody. And custody can never be willed. That is for the court to decide. The ones in the will can ask for custody but it is up to the court.
The parents have assumed joint custody.
Yes, if the court feels it would be in the best interests of the child to award joint custody.
No, as both signatures are required on the passport.
It can if there's a concern for safety or health. Why not grant the child joint physical custody of you? see related link
WHY, were you denied joint custody? There must be some reason that a custodial parent would then be denied joint custody.
As the father has joint legal custody of the child he can not say he does not want the child at the paramour.
By determining that the right of a parent to primary custody of the child supersedes the best interest of the child.