DS2 is 13 months now - we had a difficult time when he was first born with DS1 who was 2.4 at the time - quite aggressive towards DS2 (biting, hitting etc) which we dealt with by ensuring he couldn't get to DS2 unsupervised, rewards. It gradually got easier and whilst DS1 has always been very boisterous with DS2 and manhandles him constantly, it has not been aggressive.
These last couple of weeks, DS1 (now 3.5) has started being aggressive towards DS2 again - this time, it is pulling him to the floor when he is standing up, kicking him to the floor when he is sat on the sofa and DS2 is stood up holding on. In hindsight this probably started as DS2 started getting on his feet much more and becoming mobile with his walker (as soon as DS2 stands up and starts walking with his walker, DS1 goes straight over and pulls him down).
Does this sound like those initial feelings of jealousy re-emerging now that DS2 is no longer a 'baby' and more of a threat??
And how the hell do we deal with it? I am back to taking DS2 with me everytime I go upstairs/kitchen/toilet