On an unknown date in 1979 Pem Yates-Briggs left from her home in Clackamas County, Oregon to search for her father in California. Pem Yates-Briggs' mother received a phone call from a California police agency asking her if her daughter had permission to cross the state line into California. The mother said Pem Yates-Briggs had her permission to cross the state line which was the last time Pem Yates-Briggs was heard from. Pem Yates-Briggs was never reported as a missing person until March of 2024.