I, unfortunately, have no children of my own - and I always feel so much for you parents going through this. My niece and nephew are 11 & 7, both skinny as rails and super-active with two great role models - but I still worry about them.
I can tell you, however, that I think a big reason I grew up with issues (I was convinced in school that at 5'6 and 130 lbs, I was "fat") that I truly did learn it from my mom. She was my role model, and in the absence of all other family (I grew up almost 1,000 miles away from my extended family and I lost my older sister when I was only 12) - she was all I had to look up to and she did not like herself at all. She constantly hid from cameras and always,
always made comments about being "fat" and "ugly" and "wanting no photos of herself taken." She hated shopping for clothes, she hated dressing up and going out, she never thought she was beautiful or worthy, at all. It makes me tear up even thinking about her low self-esteem...and I do NOT blame her for MY problems...but, she is who I learned everything from. My mom is an
amazing woman, who fought through so many challenges in life that I cannot even comprehend. I have no idea how much she weighed back then, but at 5'5, I would guess she was probably 160-175. She wasn't huge, she wasn't ugly and she never believed it (even with my dad telling her she was gorgeous all the time!) - she still doesn't.
You're a great mom for realizing this and trying to make sure it doesn't happen to your kids, most definitely! But I'd have to say one thing you can do for them is be a role model in every way - no negative talk about your own looks (or others), smile huge in every photo (even when you feel fat), always partake in life (no matter what your size) and be self-accepting always.