My son will be turning 4 in July. Up until recently, he has been fairly placid & good natured when playing with other children, eg sharing toys, allowing other children to use his things, etc.
Over the last month or so, I've noticed that he seems a bit more 'aggressive' when playing with other children. For instance, his two little cousins came over to play last weekend, and he wouldn't let them play with his toys, even though he wasn't using them at the time - he even pushed his younger cousin away when she tried to touch one of his toys and got a bit aggravated about it. A few months ago he wouldn't have cared less if someone played with his stuff.
Also at an indoor playground yesterday, ds was playing on a wooden train (big enough for a couple of kids to play on) and when some other children came and climbed on it, he yelled at them, "Go away, it's mine!!!!" He seemed really agitated about it and wasn't satisfied until they jumped off and went away. I walked straight up to him and told him that it wasn't his train, that it belonged to the playground and he had to share it with the other children. He's been doing this a lot lately but I just don't know if it's normal (for his age) to be like this. I keep reinforcing to him that he has to 'play nicely' with other kids and share things with them.
Does this sound familiar to anyone? I guess I'm just concerned about him becoming a bit of a bully, or am I worrying too much? Thanks.