W.C.
A couple of things.
1.) They are four...there is little quiet time for most kids.
2.) Be thankful that you have a DIL that is so into her children. She is obviously a good, loving mother.
3.) Enjoy this time with your family instead of being stressed out. This laughter is the greatest gift that they can give you. Enjoy it, it doesn't last forever.
4.) Don't speak to your DIL about it...Do speak with your son about it. He should be able to talk to her about it without drama.
5.) You can always (kindly and upbeat) suggest that they head outside to act like this. or have coloring books, or reading books for them to play with when they get to your house. They will want to play with these immediately. This is a settle hint…hint. You can hand them some bubbles when they get wild and tell them to go outside to blow some bubbles. Another good hint...hint.
Try to remember that this is their family time too, and in these days, that time can be so limited. You don't want your house to be the place that the kids go to sit. I loved my grandmother, but her house was a sitting house. I hated going there. I love her, but hated going to see her. You might find that they come over less if the kids can't be kids there.