I also think my BIL's father was a tyrant who truly didn't let his kids be kids, sometimes people can't help it because of how they were raised. When his son was 12 the courts let him decide where to live, with my sister and bil he would have had a huge house and a lexus...he chose his mom...that tells you something.

My sister never had her own kids but she has always been good to mine so has my bil but when they were toddlers and would misbehave it would bother him too...I already told my daughter when the twins are terrible two's she will have fun with her uncle. He does seem to have extra animosity for my nephew though. My falling out with them was actually because of how mad my hubby got at my daughter during her teen years which is funny actually.