MIL is telling my son to keep secrets and “don’t tell anybody.”

Tell him AND mil that “secrets” aren’t permitted. Let her know that teaching him to keep secrets can put him in danger. We don’t do secrets - nothing is ever off limits to talk to mom and dad about. Surprises are different and ok.

unfortunately they don’t respect ANYTHING I say. And then they play victim every time I do say something.

That’s super hard. Can you explain the dangers to your kiddos dad and your kiddo? Hope that dad passes it on?

said it perfectly.

I would try talking to dad about the safety concern regarding MIL trying to keep secrets, etc. If they aren’t respecting the boundaries that involve safety (because it may be an innocent secret today, but now your kid is learning that secrets are fun/okay, so when a dangerous secret arises, they won’t know the difference), I’d personally be taking it to the courts. Full custody if dad can’t be trusted to help enforce safety concerns.

he 1000% backs his mother and her behavior and constantly disrespects me particularly when it comes to parenting. One time she called herself about to butt in a conversation and for the first time he said “I got this” and she threatened to kick him out so he gets mad and takes it out on me as if I’m causing it. He refuses to see how she is. It’s like she can do no wrong in his eyes despite all the wrong she’s doing. They act like they want to push me out of the picture and like I have no rights to MY son. They belittle me in front of him. Disrespect me in front of him. Then make it seem like it’s me being the bad guy when I do/say anything to mother him. How do I go for full custody when we coparent?

You would have to prove why he doesn't need as much time with his dad to limit his time and that's hard to prove. Unless you can prove your son being with dad is detrimental to him, it's hard. You also can't keep MIL out of his life as long as dad allows it. Trust me, it's hard to deal with. My ex is with a woman (whom he cheated on me with) that flat out told my girls their brother can live with her and his dad because they don't like redheads (my girls are). They've told my kids they are dirty and disgusting and said horrible things about me to them. And I had little to no say on her being around my kids. It's absolutely terrible. You can try to talk to MIL and ex and explain why keeping secrets is bad but regardless, always keep your relationship with your son open (without bad mouthing dad and inlaws) and always remind him why it's important to not keep secrets from mom! Always!

I would tell MIL “we are teaching our son that the people who ask them to keep secrets especially from his parents aren’t healthy people to be around and we would appreciate you not asking him to keep secrets so as not to confuse him”. That way you tell her in no uncertain terms that you aren’t messing around but give her the benefit of the doubt and a chance to change her behaviour. If that doesn’t work, absolutely start building a case for legal action.

Are you and the dad together? If so yall need to set boundaries with his mother

no we’re not together and as mentioned in a previous comment, he goes against everything I say/do and goes with whatever his mother says/does.

I would tell your son about secrets vs surprises and let him know surprises are ok and are revealed quickly but secrets are not allowed. Then ask your son to tell MIL what he's been learning about secrets and surprises and let him recite it so she KNOWS that your son knows what the difference is, that secrets from mum aren't allowed and that he is to tell anyone asking him to keep a secret 'no'. You might also want to discuss with him how to recognise 'tricky' people as it sounds like she is one, it helps kids to feel and be safe around problem adults.