Siobhan is the lead singer of Flashin' Midnight, and George's girlfriend. She was portrayed by Anna Cyzon.
Season 9In Degrassi Takes Manhattan, George implies that he had a nasty break up with her. She was the lead singer of Flashin' Midnight and left after their break up, which is why George temporally replaced her with Jane Vaughn. However, when he and Siobhan get back together, she retakes her position as lead singer back, leaving Jane without a band again.