My Dd is 8 (9 in March) and has been like this for 18 months, the first things we noticed was that she had a lump in her breast, and she was referred to see an endocrinologist unit at the local hospital.
The consultant was great with her, checked her all over, blood tests and scanned her hand- this tells them the childs 'bone' age and this tells can tell them whether there is a likelihood of puberty hitting early and said yes she was going into puberty early, but nowadays it's nothing to worry about.She was discharged in May last year.
Since then she's also got the greasy hair,spots appearing and has had to start wearing deoderant, also her breasts get very tender, and are starting to grow more noticeable.
Over the last few days she has been complaining of feeling generally 'odd' (her description) and been very tearful.She has had bouts of moodiness , very like PMT for about 18 months now, but this bout seems to be much stronger.
I'm pretty sure the periods will appear very soon, as remembering back to when mine started I had the same general symptoms.
The only 'puberty' related signs that haven't appeared is the body hair, I can't remember if that came before or after my periods started, but I guess things can happen in a different order.
Dd is quite tall and slim for her age, many people think she's about 10-11. Whereas I stared my periods at 11 and am only 4' 11.
There are a few threads on here about this topic, and I am thinking of getting her some of the 'Teen' vitamins to try, to see if that helps make a difference. Her Consultant advised me to give her Evening Primrose Oil capsules, to help with the breast tenderness and moodiness , but to be honest it didn't really make a difference.