I just can't help it...

Today I was at the pool with the kids.  There was a very chubby boy there.  He turned around and had some very obvious plumber action going on.  Kate immediately pointed and laughed so loud!  Ella was laughing along,  but I grabbed Kate's hand right away and told her to stop laughing.  I said, "some people just can't help it." Very solemnly Ella said, "yeah, Kate, like I just can't help laughing."