Caitlin O'Leary is a witch who cursed Tommy Murphy and his descendants 100 years prior to modern day. She cursed the Murphy family as Tommy Murphy accidently made her angry after a series of unfortunate events. Then, she cursed the Murphy family with bad luck so that "anything that can go wrong, will go wrong." They do not agree with this. Tommy accidentally angered Caitlin at the dance a 100 years ago by kissing another girl, hurting Caitlin's feeling. And when she try to walk away Tommy tripped and ripped her dress in front of the entire crowd, which it embarrassed and hurt her. Also, it finally angry at Tommy. She flipped Tommy's "lucky" coin and said that he will forever suffer eternal bad luck and his descendants. A few years later, Tommy tried to ask her to forgive him and to reverse the curse. but he was too late, for she was married to another man and this leaves Tommy feeling sad.