Posted 17 December 2012 - 08:31 PM
I also would not leave your 3 yo with the baby. He is showing you he can't be trusted not to harm her, so keep her safe.
I have a boy and baby a similar age. He is pretty good now at not being deliberately rough, but now more into rolling him, trying to pick him up or wanting to jump over him. We have been using natural consequences - if you are not being gentle with the baby, you can't have xxx as you might break it. The xxxx that has worked for us is a go on mum's iPad. He has lost goes on it for weeks at a time and also had some games deleted, and knows he needs to show gentle behaviour to the baby for games to be put back on. Plus we do all the positive reinforcement stuff, give him some time with us in his own.