There is no should everyone is different - some 13 year olds have essentially no size. Puberty hits people at different ages from early to late. Some adult women have large breasts and some have essentially none.
how can girls get big breast
I think around 32A and 34A. I am 12 and I am a 34A.
I think that a 16 year old girl's breast areola size should be around a size 16
one way is to go to this breast machine and tell them how big you want it
it depends on how they have developed but normally 30-36 A.
you can't its just how humans work. He can pay for her to have breast enlargement surgery !
Consult a physician
It's genetics.It's in the genes.But, in the last decade or so, breast size has increased due to hormones put in cattle.
because they are developing in order to be able to provide milk for baby later on
because when they get pregnant their boobs fill with milk and they need lots of milk so that's why girls have big boobs!!!
The size of your breasts is predisposed in your genes.
They don't. However, girls who wish to exhibit that fake "Barbie Doll" look that some men are attracted to, tend to go in for such "enhancements" as breast implants, lip fillers, and bleached blond hair.