At what age did your boobs sprout?

My boobs are small and I started puberty pretty early. My boobs haven't gotten any bigger. My family well, my sisters and mom, both my sisters ( who are older than me) have some what of big boobs but my mom has them a bit bigger than average. Also my sisters have a different father than I do idk if that could be a difference in our boob sizes, because of genetics. Also they all use push-up bras and I use normal bras. I guess cause I'm younger. Also my mom never buys me bras or panties. So I somehow have to find or earn my own money but I can't have a job I'm not 16 yet. 
 
But thank you guys all for your time💘
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