Is breast size and the age you get it determined on a gene?

Question:

My sister had well developed breasts at the age of 13, and same goes for my mother. They both have breasts larger than the average size, yet my mother's sister is quite flat chested. I should have breasts by this time, yet I don't. I'm wondering - could I possibly have inherited my aunt's flat chested-ness? I do have breast buds, though.

Answers:
u might have but breast dont develop right at 13 u have 2 wait it out plus we guys dont care about breast size it is personality and stuff like that so dont worry

Not always. Do not depend on how your family looks to figure out what size you will become.

My family were all C cups or lower, I ended up a J cup.

Don't worry about your size, even barely a handful is perfect.

Each girl develops at her own rate. Size may be based on genes (but genes have no effect on when you start developing). Don't worry. You WILL grow eventually. breasts develop until a woman is in her 20s, so you have lots of time.

Is breast size and the age you get it determined on a gene?

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