I can't remember when I started mine, but dd is 14 and has just told me she's a bit concerned she hasn't started yet. I thought 14 was quite usual - am I wildly out of date? She is 5'4 and I don't know what she weighs but about average, I would say, looking at her friends. Certainly not skinny. She has breasts and hips and body hair, so she's developing in other areas, just no periods yet.