I'm babysitting a 5 and 3 year old, and they are complete opposites of each other. They seem to have fun when they horse-play, but this leads to fighting and crying. What troubles me most is the lack of "our'' toys. He has his toys, she has hers, but she likes to play with his toys such as balls and toy sacks and he flips out when she touches it, even when she was already playing with it first.

Is this normal behavior for children? I remember having a ton of toys that my brother and I shared. My brother and I would always play cars and army men together, and we had a stuffed animal we would bring to life and play together, even though that was really my brother's toy.

I don't remember ever fighting with my brother over toys because we always shared.

As a babysitter, what do I do when they are fighting over toys? Should I introduce toys they can play with together? If so, what?