bullies?

If you know me, you would know that I love babies and happen to babysit three at times, but I mostly babysit one. There was one time where my nephew was getting on my nerves and I just happen to be really really tired, so I was getting really frustrated. I really really love my nephew but I guess stress just got to me because I didn't care if he cried, I just put him in the bed and gave him his milk(because I saw him yawn), he, of course, cried. I kept on doing the same thing for three times until I guess he must have been really sleepy (like I predicted) and just went to sleep. I can't feel but feel a bit bad because I caused him to cry. Today, my brother had a few people visit his house and those people brought their kids. The kids were a lot older then my nephew so I thought they would understand not to be rough with him. They were warned by their mothers to be really gentle and careful around him, but while their mothers couldn't see, they would push my nephew. I don't know why but I didn't tell anyone. What's worst is that they actually tried to act all innocent and if they're mothers were watching, they would try to hide pushing my nephew, they made it look like they were actually playing with him. I don't know why I have such strong feelings about this,I guessit's because my nephew looked a little out of place and alone like I sometimes do when I'm with my cousins I don't know if you think I'm totally wrong, ok everyone has their own opinions so please don't judge!
Sincerely,

Citrene