(Federal Way, WA) -- Authorities say a woman who was killed in a crash in Federal Way, Washington Saturday morning was the sister of former University of Washington and current Boston Celtics star Isaiah Thomas. Police say 22-year-old Chyna Thomas was heading south on Interstate 5 north of 288th when her car went off the road. The vehicle landed on a barrier and hit a pole, and Thomas died at the scene. The crash is still under investigation.