see, the mom screwed up by not pancaking the kid immediately, the moment he stuck his fat finger in her face.
it's like the teacher who gets their ass whooped by a student. before the kid swings, there's usually a whole series of steps - intimidating looks, verbal threats, standing up, getting in face, etc, as they test their boundaries.
lesson learned... whether it's a man in a bar, your kid, whatever. The minute they test their boundaries, you make them see stars.