I never saw my paternal grandparents ever go to church, and my dad and his younger brother seldom went to church either. My dads oldest sister was a devout Catholic as were her daughters.
My maternal grandparents went to the Hillyard Christian Church as long as they could. I don't remember grandpa going much, but I was pretty young when he died, but he was listed as one of the founders of that church. My grandmother lived 30 years longer and went to church almost every Sunday, served on the sunshine committee, made quilts for sales at the church (she bought several of them so I still have them).