She is not below average so that is good, my son was a chubby baby but spent from preschool on being under the growth curve for weight and height. He suddenly, since last summer has had huge growth spurts and is in the 80th percentile for body mass index. He is perfectly healthy but from going below the 5th to this in half a year is shocking!
BUT, last year when he was still so low at age 14 we did go to an endocrinologist to make sure he was ok. THey did a hand xray to see if he had overall delayed growth or if his bones were average and he was under the curve, turned out he was slow to grow overall so they just said wait till the growth spurt. And they were right.
As for the head thing, when he was a toddler, he did have a head that continued to increase and at age 2 he had the head size of an 8 year old (it is now perfectly fine).
So what I will say is scary but remember he had symptoms that made it clear there was something wrong.... he started having seizures at age 1.5 and they got worse and worse, his overall development slowed and he started having head banging and serious problems....
When he was 2.3 they finally got a neurologist to do a CAT scan and they found a huge mass and his internal pressures were super high. They feel they had been high for months. I know two other people that had similar issues so it is not unheard of but very RARE so dont freak out. Of course I would meet people like that because we go to therapy places where the odds are higher for me to meet such people.
If she is not having headaches, or seizures or any neuro signs I would not be worried. But it is pretty easy to check out if you are worried and not worth losing sleep over.... if you have any concerns about her growth or development physically of course, just like with the neuropsychologist evaluation, get a neuro and endocrine exam too.
