I don’t know. Since I have had CPS sent to my door because of things my son lied about at school I can see that being inflicted with CPS is a real pain, even if they agree that what the child said didn’t happen. What I would do is keep a closer eye on Joey just to see if you so see any unusual bruises, and I might later on try to approach your son about it again. He may have shut down because Joey told him not to tell, or it could be he used the word butt and thinks he’ll get in trouble, or even because you perked up your ears when you heard him say it.