I have two younger brothers. One is twelve and the other is ten. They used to get pretty annoying. The youngest would always act like mom's little enforcer. If I got in trouble for something, he would tell me Mom wanted to talk to me. Whenever he would tell me, I would usually be busy and tell him to wait. He would then go tell Mom that I was ignoring her when I wasn't.
He would also try and wake me up in the morning by spraying me with cold water. I would usually jump out of bed at him, and act like I was going to beat the crap out of him.
The older one, is known to be really ungrateful. He's picky with his food, and complains a lot.
Oh well.