B and Z were having part of their ongoing backseat battle (including, but not limited to: kicking, scratching, name-calling, toy-stealing, and hitting).
In a moment of parent-induced truce, I told Z he had to apologize to B. He did so immediately and stuck his head back in a book.
B started complaining a few moments later, that "I didn't hear him apologize, so he didn't do it. He has to do it again so I hear it".
If a tree falls in the woods and B doesn't hear it, did it really happen?