December 11, 2012, 6:56 amThe 17 year old grandson of a Milwaukie woman has been charged in her death. Andrew T. Johnson was arrested last night near Janzten Beach where he was visiting friends. 63 year old Donna Irene Tennant's body was discovered around noon Monday when police made a welfare check at the request of a relative. Johnson lived with Tennant and was supposed to be attending community college. He faces aggravated murder charges and is being held at the Clackamas County Jail. We don't know how she died. An autopsy will be performed today.