Her grandson and heir John Bonham - Christie had plans to develop the island .
Mary Bonham - Christie died in 1961 , aged 96 years , on the day that her family had arranged for her to be moved to a nursing home off the island .
Mary Bonham - Christie 's grandson Mary Bonham - Christie Mary Bonham - Christie       Christie had plans to develop the island .
Mary Bonham - Christie died in 1961 , aged 96 years , on the day that her family had arranged for her to be moved to a nursing home off the island .