Slow hair growth in 3.5 year old girl

[Stagiaire]

My dd will be 3.5 next month and her hair just will not grow. A lot of the other girls of her age have long, thick hair tied up in pony tails and bunches. Her hair is still very short, like that of an 18 month old's. I honestly have not seen another girl her age with hair that short. With her starting school next September, I am concerned that she doesn't start reception with toddler hair! She eats well, fish, nuts, eggs, veg, fruit, chicken. We have red meat once a week and my kids don't drink tons of milk - could this be the reason? I don't think it can be as a girl at the school who doesn't eat any dairy has heaps of thick, lustrous hair! My older daughter also has fine hair for her age but no way as short as my youngest. Can anyone offer any advice or just some reassurance that it will eventually grow??

My DD1 is exactly the same.Her hair is blonde, thin and very wispy and has never been longer than chin length.She will be 4 at Christmas.
It cant be diet etc becuase DD2, 2.5 has lovely smooth hair that is already quite long.
I had DD1's hair when I was young and it didnt really thicken up till I got to about 10, but did grow a bit.It helped mine (and is slightly helping DD1's) to cut it regularly.This is the last thing you want to do as it obv leaves even less hair, but it does stimulate growth-DD1 actually has an acceptable looking bob for the first time ever because I have been trimming it minutely every 4 weeks or so for the last year.

On the bright side, DD1 doesnt seem to notice toon much.She occasionally asks for a bobble or a plaitn or whatever but nothing more than that and has just started nursery class at school and no other kids have said anything-they dont give a fig at that age.
Hope this helps.

What's your hair like and her fathers? It's not unusual for the hair to be slow growing. Have you had a thyroid test and full blood count done to rule out any underlying issues? But my guess is it will suddenly come. I know a few children who have had spikey thin hair till about four and then suddenly overnight it seems it comes in thick and fast.

Thanks for your comments. My hair and her father's is pretty thick and was definitely faster growing at that age. I will try the trimming thing, that's something I haven't been doing. She's NEVER had a proper hair cut. Just 2 tiny trims in her whole life! Will mention to GP next time we're there too just in case of thyroid issues.

My DD is 7 at Christmas and her hair is still not down to her shoulder. I get fed up with people commenting e.g."her hair would be beautiful if you let it grow" or does she not like long hair.
My hairdresser told me that hair grows in different phases and it will get longer eventually.
HTH

I only have 1 DS but my observation of his friends is that for some unknown reason girls hair seems to grow/develop much more slowly than girls?