I don't know how you can be struggling with bottoms now I've seen your post ref what her friends wear, leggings, joggers and cargo pants are the easiest and most forgiving clothes , sweatshirt and tees hide so much especially with an open zipped tracky style top or hoodie to make her shape flow.
Your language about her shape and body, the words you use about her stomach 'flabby' ,'awful', weight 'out of control' lead me to believe that this clothes problem is more of an issue for you than for her.
Please consider your beliefs about looks and weight. Like the poster here who used the word 'horrific' ref your DD's situation.
Hope you don't tell her this about her tummy or use this language around her.
You say 'Really struggling',
But seriously, none of these styles are inaccessible for an 8 year old carrying extra weight, all of them have elasticated waist. She couldnt have chosen a better fashion era than now.
jd sports, sports direct etc all have massive sales on.
Vinted has all the latest brand name kids leisure wear too, so much cheaper and often like new because kids grow so fast.
Experiment with sizes, buy in boys range as they're exactly the same but often slightly bigger waistband.
tops , hoodies and jackets in boys ranges are usually longer, so great over leggings.
for some reason they seem to crop EVERYTHING in girls and women's sports gear.
buy women's small sized bottoms or just size up in kids' section and hem the legs if too long.
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