How to stop breast sagging?

Okay this is a weird question because I'm only 14, but I'm a bit overweight and all of my weight goes to my boobs and my stomach. I naturally have pretty small breasts (my mom does too naturally) , I'm working on losing weight and my boobs are really big and saggy. They are not perky at all and do not stay up without a bra. When I lose weight will they stop doing that? i have always been a chubby girl and I hope my boob size will go down also when I lose weight. Will they? And will they stop sagging when I lose the weight? Thank you!
How to stop breast sagging?
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