Reports surfaced on Wednesday that Mueller and her twin boys, Bob and Max, 7, were missing, but later in the day the Utah Department of Public Safety released a statement that they had been found.
"Troopers with the Utah Highway Patrol responded to the welfare check call and located Mueller, her two children and a nanny on Interstate 15 near Nephi, Utah," it said. "The children are safe and will be released to family. Mueller was taken to an area hospital for evaluation. The State Bureau of Investigation is currently investigating the incident. We do not have any more information to release at this time."
A request for comment from Sheen's rep was not immediately returned to ABC News, and the usually vocal actor has been silent about the incident on social media.
Mueller, 38, married Sheen, 51, in 2008, but divorced just two years later. Mueller has also been to rehab in the past, according to People magazine.