At a family get together tonight my sister decided she would take my daughter's hair band out and…

At a family get together tonight my sister decided she would take my daughter's hair band out and let all of her hair down out of her pony tail. I have a brand new baby and I went to all the trouble to comb it and put it up nice and my sister just took it out. So I said to her, "you just took her hair down? Why would you do that?" To which she responded, "I saw you take it down the other day when she asked so when she asked I did it." 1. I'm her mom. If I choose to take her hair down that's one thing. 2. She asked in the middle of the mall while we were talking to some relatives we knew but barely ever see. It was not a time where I wanted to fight the hair battle with her. 3. No matter how many times you see me make a decision about my daughter, you have absolutely no idea what my thought process is behind it. You never just get to assume you know what I'd want for my kid, unless I've actually told you...I'm sure I'm overreacting but I can't seem to help it.