Tammy Lynn Lamondin‑Gagnon was 20 and newly living with her family in Newmarket, Ontario, when she disappeared after a night out on Friday, May 28, 1999. Described as industrious and interested in yoga, poetry and numerology, she worked two jobs and was taking driving lessons. She was about 5 feet 6 inches to 5 feet 8 inches, slender, with blue eyes, short wavy brown hair, a dolphin tattoo above her right ankle, and navel and ear piercings.

Tammy was last seen by a wider group at a house party in Stouffville. According to Pol Classen, who was among that group and later became the focus of suspicion, he drove her to Fairy Lake Park in Newmarket and said he dropped her off around 2:00 a.m. on May 29, 1999. York Regional Police searched the lake by divers but found no linked evidence. Classen was questioned twice, reportedly rented a carpet cleaner after the disappearance, and told friends he had seen Tammy around town; those claims were not verified. He later died by suicide before any arrest.

Her family searched, hired a private investigator, held a memorial more than four years later, and applied for a death certificate in 2015 after 16 years without contact. The case remains open with York Regional Police homicide. Does anyone have memories or information about Tammy that could help explain her last known hours around Fairy Lake Park?