Correspondence with Mary Soames [earlier Mary Churchill], mainly on her and RSC's respective books and family research, including: family homes; [Arthur] Christopher Soames not being shortlisted for the South Kensington [London] constituency, Nov 1967; the libel case against Edward Mylius, 1910; CSC's friendship with Walter Sickert; the date of WSC and CSC's move into Admiralty House, c 1913; avoiding conflict over their use of family papers.

Other correspondents include: Christopher Soames; [Reginald] R V Jones on his memoir of WSC for the Royal Society (3).

Also includes: a list of houses where WSC lived; a memoir of WSC by the rector of Ellesborough, near Chequers [Buckinghamshire]; various transcripts and copies of letters on WSC and CSC's engagement; copies of CSC's letters to her sister Nellie Romilly [earlier Nellie Hozier] and her son Giles Romilly, 1928-60, on subjects including the Second World War, RSC's engagement to Pamela Digby [later Pamela Churchill, Pamela Hayward and Pamela Harriman] and Nellie's failing health; paper by R V Jones on WSC and science.