Hair pulling to calm down

Does anyone else have a child that does this? My 3 year old started doing this around 10 months and he plays with hair to go to sleep or when he has anxiety or nervous. He has sensory processing disorder so idk if that is why he does it. I guess it calms him down. But he does it every night and has to do play with my hair. Im starting to lose my hair cause hes constantly pulling it out on accident cause it gets wrapped around his fingers. Idk how to make him stop. Dont know of it's always gonna be like this or if he will grow out of it