Hello, Colin-
Rt Rev. Henry Mosley, Bishop of Southwark, married Mildred (d. 1963), dau. of Edmund Willis, curate of Horsham, great-grandson of Francis Willis, M.D., who treated George III, and died 1948, leaving: (Mildred) Betty, born 10 Sep. 1909, educ. North London Collegiate Sch. and Cheltenham Ladies' Coll., D.B.E. (1975), m. 1929, Rev. Michael Ridley (d. 1953), rector of Finchley. Simon was their eldest son (of three; also one daughter).
Fuller details for reference:
Debrett's 1985: Countess Leonie Virginia de Bosdari married secondly, 1975, Rev. Simon Ridley, M.A., B.D., of Ford Brook, Burnt Oak, Crowborough, Sussex. They lived more recently at Oxney House, Wittersham, Tenterden, Kent. He was based in the late 1960s in Hong Kong, and also at Christ Church, Taipei at some point.
1959 marriage between Simon Ridley and Katharine M. Coldstream; births with mother's name 'Coldstream' in 1960 (of Rebecca) and 1962 (of Katharine) as in the death notice.