Santa syndrome is a psychological syndrome in which affected individuals to ultimately accept atheism. Most individuals discover or are told that the supernatural aspects associated with the Christian tradition of Santa Claus, such as him riding a sleigh led by reindeer and giving all good children around the world Christmas presents, are legend and are simply practiced in order to enrich the experience of celebrating the holy day. However, individuals with Santa syndrome are often abnormally bitter about this finding and as a result, move further to reject the existence of God, which has been firmly established in the Five Ways, Kalam Cosmological Argument, etc.
The militant atheist came to deny the existence of God after suffering from Santa Syndrome in his/her youth.
A person who conclude god isn't real when he finds out santa isn't real.
There's no good example for Santa Syndrome.