Is it normal to be angry at my brother when?

My brother and his wife have two young girls one who is almost three and one who just turned 1. They are also expecting another as well. My daughter is three and is 4 months older then my brothers oldest.

Here is the problem I really dont like the way my brother and his wife treat their kids. I never really said anything because i didnt feel it was my place untill...

We were visiting and my daughter became upset and started to cry my brother who was stressed at the time looked at her and told her to "shut the f up!" He also said things like "You are such a baby" etc. I was shocked that he would talk to MY child in this fashion and asked him to take us home.

Is it normal that I am furiuos with the way he spoke to her? Should I try talking to him about it? Totally confused. (This is normal talk between him and his own kids)