Sofie Mortimer (9 October 1983 age 20) is Norman Slikk's girlfriend and likes to listen to Troy Sivan. They met when Norman was on Redshirt Senior year of 1995. Leopold sometimes hate her for her love of Justin Bieber and Troy Sivan.
- In The Slikk Winter Party, she helped Leopold and his brothers carry party stuff.
- In Leopold's Cousin's 4th Birthday, she was with Leopold when he shoots bubbles to Norman with his machine.