She wants one. She wants one because my sister told her she needed one

She has teeny, tiny, little breast buds. Not enough to warrant them needing any support.
My sis thinks she will be bullied at school for being the first to have breasts. Surely being the first to have a bra would make a her a target even more so?
I'm thinking crop tops will suffice for now, if dd1 really feels she needs to cover herself? She probably doesn't even have enough to actually have a bra size.