Diana Robertson/Mike Reimer
On December 12, 1985, Mike Riemer, 36, his girlfriend, Diana Robertson, 21, and their daughter, Crystal Robertson, age 2, traveled from their Tacoma home to Pierce County, planning to find a Christmas tree. Later that evening, customers at a Kmart store 30 mi (48 km) north in Spanaway found the couple's daughter, Crystal, standing outside the store entrance. When asked where her mother was, the dazed two-year-old told her grandmother that her "Mommy was in the trees."
On February 18, 1986, over two months after the couple's disappearance, the body of Diana Robertson was discovered half-buried in snow by a motorist near a logging road off of Washington State Route 7, just south of Elbe. Riemer's pickup truck was also found near Robertson's body.
On March 26, 2011, hikers discovered a partial human skull later determined to be that of Mike Riemer. It was found in an area within a mile radius of where Robertson's body had been discovered in 1986.
After recovery of the skull, Lewis County investigators stated that they believed Riemer could have been a possible victim of homicide as well, though his cause of death could not be determined.
Based on the condition of the skull, however, authorities were able to rule out a gunshot wound to the head.