Is this hairstyle NPC exclusive? Or is it bugged out from hairstyle selection

I also found this weird. My sims grown up children end up having the spiky boy hair, and one of the children that I moved in had a ponytail that was in other sims games. I am confused because I cannot find this hair in the inventory so I can’t change the color or anything. I want to know where the hair came from and why it is hidden. I don’t want to risk losing the special hair so my sim is stuck with it because it is pretty. Sorry at the moment I do not have a picture because the file size is too big.