Lady P finally has a bit of hair four boys and two and a half years of waiting we finally can get it all into one albeit very slim ponytail

It is very fine and she has little ringlets but it is also very fly away and has no particular style so it cant be left down. She has the cowlick from hell so a fringe is out of the question as it naturally sweeps to the side.

I am just wondering is it a myth that cutting hair encourages growth? I dont want to chop it now seeing as it took so long for her to get it but if it will help thicken it and tame it a little I could be convinced

Any advice greatly appreciated