Nearly one month after notorious murder cult leader Charles Manson passed away on Nov. 19, we have now learned what finally caused the 83-year-old’s downfall after more than four decades behind bars. According to the death certificate obtained by TMZ, Manson had been suffering from metastatic colon cancer, which eventually lead to respirator failure and cardiac arrest.

His death was originally attributed to natural causes one week after it was reported that he was hospitalized, and spent four days in the hospital before dying. Apparently the cancer was something he had been struggling with for quite some time. Nine months earlier, it was reported that Manson was in need of surgery for internal bleeding. At the time, he was considered “too weak” for any procedure and was sent back to the Bakersfield prison. It was then speculated that the end would soon be near for the infamous killer — and, like many predicted, he didn’t live to see 2018.

Interestingly, the death certificate lists both of Manson’s parents as “unknown,” but we do know that before his life behind bars, he fathered three sons named Charles Luther Manson, Charles Manson Jr., and Valentine Manson. His oldest son, Charles Jr., ended his own life with a “self-inflicted gunshot wound to his head” after years of trying to escape his father’s legacy. Little is known about his two other sons — though both were said to go to great lengths to dissociate themselves from their father and his horrific crimes.

Manson’s only known living relative is his grandson Jason Freeman — though it’s unclear whose child he is. In an interview with the New York Post, Jason expressed frustration that he wasn’t able to see his grandfather one final time before his passing. “It’s a little rough for me right now,” the 41-year-old explained. “It was hard because I didn’t get to see my grandfather before he passed, and that’s something I’ve been working really hard at during this last year.”

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