A GRIEVING daughter has spoken of her 30-year search to find the ‘serial killer’ behind her mother’s murder. Melissa Silva-Delgadillo, was just four when her mother Deanna Butterfield, then 21, was raped, strangled and dumped in Tilden Park, California in 1987. The police investigation, initially hampered by heavy rain, led nowhere and the case eventually went cold. But Melissa, who only learned the facts of the killing as a teen, refused to give up and promised to solve the case herself… Melissa’s hunt for justice is the subject of a new documentary featured on Truly.