Investigation reveals no alcohol or illegal drugs in Robin Williams ' body . Oscar-winning performer . Actor and singer died August 11 at age 63 . Williams was diagnosed with depression , anxiety , early Alzheimer 's , widow says . Beloved Robin was buried deeply after death .
Investigation reveals no alcohol or illegal drugs in Robin Williams ' body . Actor and singer died August 11 at age 63 . Williams was diagnosed with depression , anxiety , early Alzheimer 's , widow says . Beloved Robin was buried deeply after death .