More: We adopted Duke at 7 months old, and we had a wonderful, loving, 8 months with him. Duke was our gentle giant, he never left my side, a true protector till the very end. We had to let him go on April 7th due to an aggressive lung cancer that we believed metastasized from osteosarcoma at his elbows that was never diagnosed. He was my heart, and my husband and I will never forget him.