Stages of puberty in girls - how long from breast buds to periods?

[citymama]

Literally from one day to the next, DD1 appears to be developing breast buds. She told me this evening it hurt under one of her "breasts" (totally flat chest). Sure enough, there was a little hard bump on one side, and I'm guessing this is the very first sign of puberty. She's about 6 weeks from her 10th birthday. I can't recall what the speed/sequence of puberty is and how soon to expect more significant changes like actual breasts, pubic/armpit hair and her period. I remember having minuscule breast buds at 10 and my period started at 11.5 which felt a bit earlier than other girls in my class.

For those of you whose daughters developed breast buds at about this age, how long till their period and first bra?

DD is pretty tall - 56 inches and about 65 lbs, slim but not skinny like her sister. She has a healthy appetite and is physically very active.

She's read the AG "care and keeping of you" book and "It's not the Stork" but I'm embarrassed to say we haven't actually talked about periods and the birds and bees. Guess I'd better get moving on that!

Would love any btdt perspectives on the puberty road ahead!