Queen Elizabeth is said to have known in her final days she would never reach her 100th birthday. The monarch, who died aged 96 at her beloved Balmoral estate in Scotland on 8 September, and a new book also claims she was suffering from “multiple” medical conditions but “slipped away” and had a painless death. Upcoming biography ‘Charles III: New King, New Court: The Inside Story’ by royal expert Robert Hardman adds the late Queen was intent on being surrounded by family and making more memories with her relatives before her death. One friend told the writer about her final days: “She had come…