Can my family keep my son from me and my husband?

My family had been helping my husband and I while we were in a bad financial situation and while I was finding good ways to cope with severe anxiety, depression, and ptsd from two previous sexual assaults. We now have a good income and my mental health is easily manageable. We co rent with my sister and bro inlaw and our son never goes without when he's with us. I've been trying for over a year to get him back in my home permanently but my family keeps saying things like calling cps, or telling me he has twin syndrome with his older cousin who's six months older than him. I've told them he's welcome to come spend the night with them and vice-versa with her but they swear it'll be too traumatic. Anytime I have him he never mentions his cousin or gets upset and it's confusing me. They've also been taking him to a church they know I do not agree with and throw a fit when I try to take him to church with me. I'm terrified of them but I'm also fed up with the bs and need some advice. Please