I am the mother of a very large and physically capable 2 year old (95cm and 16kg). He has always been a really lovely boy, and still is most of the time. The problem is that he goes very suddenly from playing gently with his 4 week old brother, to shaking him, hitting him or just lying on top of him. I can't turn my back for a second. I know that usually he just forgets how big and strong he is, but that doesn't help my stress levels.

I don't want to smack him for being too rough, it seems like I am sending the wrong message. However stern talkings to and being sent to the 'time out' room don't seem to be helping.

Any suggestions on how to make him understand that he needs to be more gentle?