If she is not the one with custody, yes.
Yes. He would need her consent if she is the custodial parent.
The parent would be charged with kidnapping.
Yes
Unless you go back to court and have the custody order reversed then yes, you could be charged with kidnapping because while the order is in effect she is acting as the parent.
Unless you have the courts and the other parent's consent you will charged with kidnapping and the children will be brought back and you will lose custody and possibly your parental rights.
Often they do. A parent can be charged with kidnapping if they take the child without the other parent's knowledge or consent or from a court appointed guardian.
That might vary depending on the laws of whatever country or state you live in; also, I am not a lawyer. If this is a real case, you better consult with a lawyer. But it seems reasonable to assume that if, for example, one parent has the right of custody, then that means that nobody else may keep the child without permission of that parent.
Not without permission from the court with agreement from the joint custodial parent.
No, you can't, especially if you have joint custody, that will be considered parental kidnapping.
Yes they can.
Yes. And the parent will also be charged with kidnapping if not sending the minor right back to the custodial parent.
A single father has no legal rights to the child. see link-------------Added: Yes. Dependent upon the circumstances, an unwed parent of either sex can be tried for this offense.