I will be going to mediation and was wondering how young I am required to let minor children fly out of state. My children are 3yrs and 6mo and their fater lives in state but wants to travel to see grandparents.

As long as he is traveling with them it is fine.

I would not send a 3 yr old and deinfitely not an infant on a plane alone. But as long as they are accompanied by a parent there should be no problem.