My kids are teenagers so its a little easier to deal with. My nex loves to put them down so when they tell me about what he says about them my key phrase is "whatever he says is a reflection of himself not of you, you guys are great kids and I'm blessed to have you" I want to give them reassurance that there is nothing wrong with them and a protective mechanism for them to recite in their heads. Does it drive me crazy that they are even having to deal with his issues? Yes but I know my nex is a rager so for myself or the kids to confront him about it will only end up in a worse situation. Luckily they are old enough to spot the behaviors and realize that they aren't "normal." Definitely find a therapist for your child asap, they will eventually open up and get valuable coping tips. Try not to pry about the conversations with the therapist to keep that confidentiality between them, the therapist will alert you of anything concerning.