By his second wife Ethel he had a daughter and a son, Sir Laurence Collier , (1890–1976), British Ambassador to Norway 1939–1950. In later life Ethel became known as "The Dragon", and then "The Grand-Dragon" to her grandchildren. She vetted all the family marriages; inspecting Elizabeth Powell for prospective marriage to Rupert Crawshay-Williams (her stepdaughter's son) she said "You are marrying into one of the great atheist families; I know you are an atheist now, but will you be able to keep it up until you die?". The bridegroom started working for Gramophone Records, but became a philosopher and writer. He was the author of "The Comforts of Unreason" (1947); "Methods and Criteria of Reasoning" (1957) and "Russell Remembered" (1970); a homage to Bertrand Russell.