这是个很有趣的故事。妈妈们常抱怨儿子爱恶作剧，说他简直是天不怕地不怕，真不知拿他怎么办。可是她们不知道，有时孩子装出勇敢的样子其实是给自己壮胆，他心里正在害怕呢。

This is a very interesting story. Mothers often complain about their son's love of mischief, saying that he is simply not afraid of anything and they don't know what to do with him. But what they don't realize is that sometimes when a child puts on a brave face, it's just a way of bracing himself for the fear that's in his heart.