But he's not celebrating the holidays as much as his past crimes, which tend to be heinous indeed.
So if you're playing Arkham City today, don't forget to stop in the basement of the courthouse to hear one of Julian's sad tales. Or, if you feel like cheating, just set the date on your console to different holidays to hear them all and get the achievement/trophy.
Did you enjoy his Father's Day tale? Tell us in the comments or on Twitter.