Peer pressure can be put to good use. I have seen it in KK when he mixes with other kids his age. They try to outdo each other in the eating department when we dine together with our friends' children. At swimming, KK was very proud when he could put his whole face into the water and the other kid can't. After XX was born, we started using XX to stimulate KK on drinking his milk. Now, he always finishes his bottle very fast, especially when they're drinking at the same time, so he can show off to his brother.
XX is still a little bit young to understand or feel 'peer pressure' but having the benefit of a sibling to role model since birth, he has developed abilities in many areas earlier. He's started to poo poo sitting on the toilet bowl. I've recently started him on a "brush your teeth before you sleep" routine, with help from KK. When KK brushes his teeth at night, XX will want to tag along and stand on the stool by the sink. I thought, might as well give him a small toothbrush (detached from the electric toothbrush) and let them brush along side by side. And he enjoys doing it.
Here are 2 videos of the toothbrushing sequence:
