Sterile Rumplestiltskin

There is a man named Rumplestiltskin and he is sadly unable to have children. He tried numerous times and then when he went to the doctor, the doctor sadly reported to him that he was unable to have children due to male factor sterility. So Rumplestiltskin today (not the same one of the fairy tale) is a professor and has adopted a few children. He was never the worst guy but sadly he is never going to have his own kids.