The half sister of actors Julia and Eric Roberts, Nancy Motes, was found dead in Los Angeles on Sunday "of an apparent drug overdose," the family said in a statement Monday. There is no official report from the coroner's office yet. The family is "both shocked and devastated," the statement continued. A coroner's official told Newsday contributor Frank Lovece that the death was reported by police "as a possible suicide," though "final cause of death is pending." Motes was the daughter of the Roberts siblings' mother and their stepfather, Michael Motes. Julia Roberts did not attend a scheduled Academy Awards luncheon Monday in order to be with her family, her representative told E!