Churches aren’t Evil places . So what is your point?

if your son-in-law doesn't know what to say to his parents you can advise him to say something like this: "mom, dad, i love you, and i want you to have a full, gratifying relationship with your grandson. however although he is YOUR grandson, he is MY son, and parents trump grandparents here. i do not want him being dragged off to church. i know you want him to go. i don't. he's my son. i win. the end. if you defy me on this i will have to limit or even end the time you spend with your grandson. i sure would hate to do that."

g

The son-in-law needs to step forward and take control of this to stop it quickly. I understand that it is a touchy situation, but either HE raises his son the way HE wants or his parents will raise him the way THEY want, at least when he is with them.

Well I would not worry too much about that. At his age he will not care if he is in church or not.