It might sound kinda cheesy, but whenever I'm helping my brothers, whether it be with a sport, or with homework, it really makes me feel good. One of the best things is being able to set an example for them. Sometimes I think it adds pressure on me to do well, but that really isn't such a bad thing if it helps me do better in life.
Probably the best thing about being an older brother is having two people to play video games, basketball, or catch with. You always have a couple of pals. Having two younger brothers can be difficult sometimes, but the good times make it worth it.