(Hillsboro, OR)  --  Police are searching for a missing mother of three.  The Washington County Sheriff's Office says 40-year-old Erin McClintock disappeared Monday morning after dropping her kids off at school in Aloha.  Police say she never showed up for work that day.  Search crews found her car yesterday about three miles away from the Tualatin Hills Aquatic Center.  Anyone with information on her whereabouts is urged to contact police.