It looks like Katy or Katie are the more common spellings in the Southern US, although Kitty seems to the standard when talking about hockey. The origin is disputed: https://worldwidewords.org/qa/qa-kat1.htm
It looks like Katy or Katie are the more common spellings in the Southern US, although Kitty seems to the standard when talking about hockey. The origin is disputed: https://worldwidewords.org/qa/qa-kat1.htm