Hormone deficiency?

[Starfish125]

Hi everyone, not sure if I'm being a neurotic mother or that I may be onto something. As not to drip feed I'll give quick background of DS health. DS is 6 years and 10 months old.
Overall I had a healthy pregnancy/birth/baby but as a toddler was found to have flat feet and iron deficiency anemia, flat feet have pretty much resolved with age and iron levels seem to have been better over the years.
He has never been the tallest of children but it's become quite apparent when compared to his classmates. Even the girls are taller than him. I measured him today and he is 112cm tall, Google says average height of this age is around 115cm so not terribly below the chart. What gets me is that his older sister (just turned 9) is quite a tall girl (75th percentile) so why is he short in comparison when she was that age? For the record I am 5'4 husband is 5.7' so yes it could be genetics but what if it's not and he needs injections to grow? I mean is it easy to get referred for a blood test etc? Not sure what to do!

[BananaSpanner]

There’s nothing to do. He has smallish parents, is a smallish child and will probably be a smallish adult. No drama, no injections.

Measure him every few months just to keep an eye on it and to make sure he is growing, albeit slowly.

Girls can grow tall earlier than boys but then stop in their early teens. He may well outgrow his sister at some point in the future.