Sir Oswald Mosley's son Nicholas married Lady Desborough's granddaughter Rosemary Salmond in 1947.  Sir Oswald  found Lady Desborough more affected than all the Mitfords put together (Davenport-Hines, p. 362, quoting Lord Ravensdale).

For her part, Ettie was mortified by the Blackshirt association of the Mosleys.  Her daughter, Rosemary's mother Monica, was always quick to emphasize Nicholas's war record  "to stress that he had fought for his country rather than been incarcerated in Brixton prison as an enemy sympathiser like his father" (ibid. p. 362).

I am currently reading Nicholas Mosley's compelling biography of his first wife's uncle and Ettie's beloved son Julian (Nicholas and Rosemary were divorced in 1974; Rosemary died in 1991).  Julian Grenfell: His life and the times of his death, 1888 - 1915 is available in a very beautiful reprint from Persephone Books with a new preface by the author.