My son is divorced, has one son. His ex wife is remarried, with 2 small girls. It was agreed that I would have my son's visitations while he was away in Afhganistan. She did not follow through. Now my son is returning and she will not let my son and grandson reunite. Claims he has plans with friends. My son has ALWAYS paid child support, and a lot, if she said "jump" he would ask "how high?" just to see his son. He is 13. She claims his grades are not good, so he has to stay and study.
How hard and expensive is it to fight for my rights as a grandmother, and he deserves to spend time with his son, and he will fall off the earth for him. His dad would love to have him full time. The son claims he would like to live with his dad, not the mom. What can we do?

Where, what State?

An oral agreement cannot change a written Court Order. I am guessing that the agreement that you take over his visitation was an oral agreement, not through the Court?

Support and visitation are two different things - unfortunately.

The Military might be interested in this. The son, at 13, has a say in where he wants to live, but the Court does NOT have to decide in his favor.

The decision - if your son files for custody - would be whatever is best for the boy.

Thank your son for his service to this Country, please.

She has to allow your son to have his visits with his child according to the court order child support agreement, if she is not allowing it, he takes her back to court

While some areas do have grandparent rights, they are generally very limited.

It is your son that has to do things here. The important question (besides location) is whether there is a visitation order in place. If there is a visitation order in place and she is not making him available for his scheduled time, then he needs to go back to the court and have her cited for contempt.

... It was agreed that I would have my son's visitations while he was away in Afhganistan. She did not follow thru. Now my son is returning and she will not let my son and grandson reunite. ...

Your son has court-ordered visitation rights which his ex wife is not allowing him to exercise? He needs to ask that she be cited for contempt of court.

Your rights as a grandmother are derivative of (come from) your son's visitation rights. In many states grandparents' rights, as such are not recognized. So you might not be able to go to court on your own, but your son sure can.

I'm reading that the Grandson is "returning," not "returned." I see this to be a question about who had the visitation with the child when he was gone. I don't see a Court Order giving those rights to the grandparents.

Yes, if the ex refuses visitation when he's back, then it's time to hold her in contempt.

But, again, I am reading "returning" and either an anticipatory question or a mis-statement.