I have a few questions. On the Tanner Stage Calculator it says I am at 2.5. When will I be in stage 3? And how long does each stage last? Also, I am a late bloomer. I began puberty at either 12 and a half or 13. My mother started puberty at 13 or 14. Is that why I am a late bloomer? Or is it because I am underweight for my age?
The length of each stage varies by individual, but generally they last about a year for girls. The start of puberty is primarily inherited, but if a person is not eating properly, it can delay the start further. The reason you appear to be underweight at the moment is because you are developmentally behind other girls who are the same age as you. Since many of them already had their growth spurt, you have been left behind until you have your own growth spurt.