YTA, not for recognising this is an issue now but for not recognising it earlier as your wife obviously did the vast majority of childcare and laundry his entire life, the fact that he was still having accidents should have been picked up around the average age most children potty train not when he was in his teens. There is a huge problem in your family dynamic that you didn’t notice this issue until it inconvenienced you due to having so little involvement with looking after him and your wife did notice but didn’t do anything about it, which is practically medical neglect at this point because there must be a physical or psychological issue behind it and your reaction on finally finding this out is to shame and threaten him for something he very likely can’t help, showing why it was probably hidden from you. You do say you wouldn’t actually tell his friends but obviously he doesn’t know that or there would be no point in the threat, which you were clearly hoping he would believe to intimidate him into compliance. But this isn’t his fault. If he genuinely doesn’t know how to take care of himself in this basic way then he should have been taught as a child so that is still a parental responsibility but likely there is actually a medical problem leading to faecal incontinence, which should’ve been picked up on way earlier and humiliating him about it won’t help. He should never have been put in this situation by his parents. It is important to get him treatment and worrying that your wife is reluctant but also worrying that she had to be so seriously ill for you to wash your own kids clothes so she is probably going through something too. Medical help and therapy is very necessary especially to deal with his feelings around such a sensitive issue and restore trust with you after you threatened him. It sounds like you will be taking a much more active role in his life and you acknowledge that you and him are already experiencing stress from his mother’s illness so family therapy could help you navigate this together.