Sister Wives star Christine Brown got candid about a lot of topics in her new book - including an addiction to oxycodone that started after a knee surgery. Brown, 53, revealed that she developed a dependency on the painkiller in 2016 after injuring her knee and undergoing surgery. "I had never taken oxycodone before - if something hurt, I took ibuprofen or aspirin," she wrote in Sister Wife: A Memoir of Faith, Family, and Finding Freedom, which hit shelves Tuesday, September 2. With the surgery, I had already fixed the problem, and it hurt, so I took my meds.