Jeannie Lattimer, Peter Lattimer's sister, is deaf, and taught Pete how to read lips. In Mild Mannered, Pete tells Myka she got him hooked on comics after his dad died. In Trials, Pete mentions that shortly after his dad died, Jeannie was soon going to go off to college. In Queen For A Day, when first meeting Pete's ex, Amanda, and hearing her surname, Myka observes that she (Amanda) isn't his sister, as his sister is deaf, suggesting that Myka, like the audience, knows little about Pete's sister beyond this fact, perhaps not even her name. Similarly, she gets no name in The Greatest Gift when Pete merely observes that his mom and his sister are going on a shopping spree for the holidays. Finally, in Shadows, Jane Lattimer speaks of "my Jeannie" whilst revisiting the memory of her husband's funeral and its aftermath.
- She is played by Llyandra Ariel Evans-Jones in her first and only on-screen appearance in Shadows.