on the road 12

Friday afternoon on a bus in Wiesbaden, granny and granddad with two small boys get onboard.

boy(looking at the nearly bald man sitting in front of him): That man has no hair!!!
granny: yes, that´s how it goes sometimes...
boy: Granddad has no hair on his head too but in his face!
granny: Yes, he has a beard.
boy: Did the hair slide down from his head?
granny (amused): No, hair doesn´t slide down.
boy: Did he cut it off then and stuck it there?
granny: No, certainly not. His hair just fell out.
boy (thinking hard): Ohh...