Thats the reason I keep my own hair at shoulder length, I can't stand tangles, I can't stand hair in my face.
My best friend has long hair, she braids it everynight before bed to help with the tangles.
I am lucky though I have a son whom loves short hair, if it gets past his ears he complains to get his haircut.
My neice is 9 she is a active little girl who hates to comb her hair, therefore her hair is shorter. Nothing wrong with little girls having short hair until they are older and can manage it themselves.
I know in our case, I have two stepsons, their mother likes their hair on the longer side, dh likes it on the shorter side (as they do not comb or take care of there hair) Usually in the summer dh will cut it short as we are active people and like to get up and go, no time to primp.
**These are my opinions, they are not legal advice**