Kitten biting my chin?

My 5 month old kitten has a thing about hiding her head under my chin. She will come up to me and push my head up then snuggle up under my chin, today she has been doing the same thing but giving my chin a gentle bite lol. It's not sore or anything but just wondering why she is doing this and if other cats do this? My male cat who is 1 has never done it, he prefers to sit on my lap if he ever gets the chance since the kitten rules me lol. Any answers? :)