Yohanna Cyr was 18 months old when she vanished from an apartment at 1715 rue Rochon in Saint-Laurent, Québec, on August 15, 1978. Her mother, Liliane Cyr, had left the child in the care of her boyfriend, Aaron Lewis, who first told Liliane Yohanna was with his mother in Washington and later said the child had accidentally drowned and that he had buried her. Lewis was questioned but released for lack of evidence.

Over the years several leads emerged and faded. In 2006 a woman said she had seen Lewis leave the apartment carrying a metal breadbox on the day Yohanna disappeared; that tip prompted a 2014 excavation of a parking lot that had been wooded in 1978 but found nothing. In 2016 an American woman who thought she might be Yohanna was excluded by DNA testing. Yohanna is described as biracial with brown hair and brown eyes and has a Y-shaped scar on her right hand between the index and middle fingers.

The case remains open with conflicting accounts and no conclusive physical evidence. Does anyone have memories of the Saint-Laurent neighborhood in 1978 or information that could help locate Yohanna?