I have to admit, reading through your post, I was surprised that the only behavior of his you mentioned was toward you. If you don't know of any behavior on his part that would make you believe your cousin was in danger, why would you ask your cousin or *her mom* something so serious and potentially damaging? You also didn't mention your cousin's age, which is very relevant in how you approach this, if you choose to. If your cousin is extremely young, you are taking a major course of action that you can never take back once her mom finds out, or you tell her, that you are concerned her husband is a child abusing pedophile.

I appreciate your protective desire to make sure your cousin is safe, but you do not have nearly enough information to make the accusation you are considering making. Please move forward cautiously and use your best judgment. If you have nothing to go on but your mom's suspicions (which may or may not be based on facts) and him tipping you at a dance club, I truly don't think you have any place approaching your cousin.

If this was your daughter I would understand you at least doing the parental check and having that talk about inappropriate touching, but you said you are not even close with your family. I also experienced my father being tried and convicted of sexual abuse, so I understand that this feels like the whole world right and you are prepared to make sure there are no other dirty secrets in your family, but please don't let that make you impulsive.

Think this through and get more information.