Thank you for inquiring. Both reasons for sex from this boy are wrong. The fact that you are in puberty, means you grew from conception [time of birth], to infancy, childhood and now puberty, all without having sex to help you grow.
Breast size just like growth is also not determined by having sexual intercourse. Breasts normally enlarge at the time of puberty in response to the hormone oestrogen, produced by the ovaries. It is therefore not true that sex would make you grow or get bigger breasts. You have a hormone [a substance that regulates body processes] oestrogen, that is responsible for that.
Do not be fooled by this boy nor compare your breasts to those of other girls because we all grow at diffrent rates.
