[MadameBusty]

I think Genetics play some part but not all of it, for example you have so many women of all shapes and sizes in both your father's side and your mother's side so you could activate any of it Idk, for me my mum's side all have small boobs however the women in my dad's side all have quite large boobs and so I inherited that gene off them but needed that extra push to get there if that makes sense