Is she eating well? If so, and you're just not seeing the results on the chart, then hang tight. My daughter is tiny. She is finally 47 lbs. and just turned 9 last week; and it's mostly muscle mass since she's a competitive gymnast. Through our pediatrician, she was also being watched for something more serious. Since birth, she has NEVER appeared on the "regular" growth chart until this past 8-yr-old check up. Our pediatrician has always said as long as she's growing on her own chart, that is fine. He did recommend we see an Endro. and that's been helpful, but honestly only to confirm that there is really nothing "wrong" with her -- just petite. Are you and your husband both late bloomers? Your pedi should be asking you that, which may bring reason to her small size. I would just continue to monitor it. If you notice that she is eating well, and continues to be, and you don't see any change in her activity levels or energy, play mode, etc. then she may just be small and petite! Which for a girl is okay! My daughter continues to be the smallest in her class. A visit to the Endo may make you feel more comfortable. They tested my daughter for thyroid levels, and also to see if she had a missing chromosone, but all were normal. Just watching thryoid, is all. She basically looked at us and said, you just have a petite daughter! Wish you all the best.