I have two children (18 and in college FT, and 21 and in college FT). My ex and I have joint custody with my address as legal residency. The children want to live with their father. We have an agreement through a mediator and I get direct support.
1. Must I change the agreement officially?
2. Can he seek child support from me when they move in with him?

First, what does the support order say about when support ends. Second, since they are both over 18 they can choose to live wherever they want.

The children are now over 18, and may choose to live where they wish.

Not all support agreements allow for payments while in college, others do, I have to assume yours does.

But yes, if they move in with him, he may go back to court to ask you to pay him support, assuming the child custody agreement provides support at these ages

... in college FT ...

I pondered over this for several seconds before I finally realized that you were trying to say "full time". At any rate, whether they go to college full time, part, time, or never has nothing to do with your question.

Does your Internet service provider charge you by the letter?


... We have an agreement through a mediator and I get direct support. ...
Was this mediation court-ordered? Did the agreement result in a court order for support?

At any rate, whether they go to college full time, part, time, or never has nothing to do with your question.


Actually it does. Since both are over 18, they may no longer be eligible for support unless the support order included until they were finished with college.