When my son was younger, maybe seven or eight, I took him to the doctor for something or other and while I was there I asked him about my kid's weight. He has always been a tall skinny dude but I was worried that he was too thin and that maybe we needed to make him eat more. The doctor didn't even weigh him; he just told me that my son was perfectly fine at that size, that it's normal for kids to be really skinny, and that it's become so common for kids to be overweight that people have lost sight of what a normal-size child actually looks like. I suspect that's one of the factors at play with all the hate she's getting! Dollars to donuts that the majority of people leaving nasty comments have fat kids or kids who are on the heavier end of the normal spectrum, and they don't know what normal looks like. Either that, or they are fat cows who hate her because she had three babies and stayed thin and fit, and they are lashing out in a way most likely to inflict pain - calling her abilities as a mom into question.