Nilosh , when a person has 2 genders or no gender it is extremely painful and therefore will have to be smiling. So does your friend smile a lot to ease out his physical pain.
"Smiling Releases Endorphins, Natural Pain Killers and Serotonin
Studies have shown that smiling releases endorphins, natural pain killers, and serotonin. Together these three make us feel good. Smiling is a natural drug."