1972 : Grave moved because first plot offered no room for other family plots . No alcohol in Mary Kennedy 's system . A medical board ruled Mary Kennedy died of asphyxiation due to hanging . Kennedy family members purchased some 50 acres surrounding the grave .
1972 : Grave moved because first plot offered no room for other family plots . A medical board ruled Mary Kennedy died of asphyxiation due to hanging . Kennedy family members purchased some 50 acres surrounding the grave .