I don't get it

I don't understand why little girls can be so mean. My poor little Sara has had a hard time with some of her friends this year. Just this week her friend decided that she didn't want to "be Sara's friend anymore". It just kills me. I could tell by the moment I saw her that something was wrong. She came running to me sobbing and telling me about what this little girl did to her. The really sweet thing though was all the kids that came and asked her if she was okay. It helped her to see that she was cared about. It really brought a smile to her face. Of course once Katie and Eberly found out, they wanted to go corner that little girl and give them a piece of their minds. Of course by the next day she wanted to be friends again. It reminds me of a story that happened last year. There was a boy that had told Katie that she could never be a vet because she was a girl. This was a boy that Eberly had in her class the previous year. Eberly and her friend Emily cornered this boy and told him to never say those kinds of things to Katie again. Never mess with family!
Katie has dealt with the same thing too. This is the first year that Katie has had actual friends that are girls. She had been playing with boys the last two years. I can't say that I blame her.
Just had to vent. I guess this is a great lesson for our kids. It teaches them how it feels to be left out. It teaches them how to treat others. It teaches them to just roll with the punches. Unfortunately we are going to meet some mean people in our lives, but at the end of the day it is our family that matters.