K.H.
Yes definitely say something to her mother , he mom is probably making comments about her own size/weight in front of the girl and not realising just how much she takes in , plus she is more than likely seeing her mom reading the calories/fat contents on everything.
She is a little girl and needs to enjoy being a little girl for as long as she can and not be worrying about her self image (she will be doing enough of that in a few years). I am all for kids getting exercise through play and not being fed sugary , fatty foods all the time but how this girl is acting is way beyond her years.