There's a contradiction between two explanations above. One says Mary McCartney died in 1956 and the other says in 1969.
THE TRUTH İS:
Mary Anna McCartney (born 28 August 1969, previously McCartney-Donald) is an English photographer and vegetarian cookery writer. McCartney is the eldest biological child of musician and songwriter Paul McCartney and photographer Linda Eastman McCartney. She's still alive.
His mother Mary Patricia (née Mohin) (1909–1956), had qualified to practice as a nurse. So it's true that she died in 1956. Daughter Mary: