Should i just forget my sister said this to me?

I feel for you, I was in a similar situation, as my older sister was, and is skinny ( not a stick ), and I was heavy (5'4 and 130 lbs). I had lost weight as well and became 111 I believe, sorry I can't remember. Anyways, just think about it this way, she's a stick and probably just doesn't get enough nutrition, and you're normal weight. There's nothing wrong with your weight for your height. Also, as for what your sister said, just come up with another dis and have a laugh about it. Good luck (: