That's a very interesting piece of information, thanks Mary-Ann; a few bits I've tried to follow up:
Mowbray Edwin Hugh Charrington b. 1918 (mother Pearman), d. 1993, of Glenbrook, Gletton Fields, Winchombe, Glos. Current references give a Rosemary Charrington as being of that same place, of whom to follow.
He was s. of Mowbray Julian England Charrington (1886-1935) of The Cottage Farm, Beckford, nr Tewkesbury, Glos., who m. 1916, Mary Harvey Pearman. He s. of Capt. Harry Julian Charrington, Yorkshire Regiment, and Helen, dau. of William Gray, of Gray's Court, York [per Armorial Families (7th ed.) 1929; this line is definitely in BLG 1965, but I don't have it and Google books is being parsimonious with what it'll let me glimpse!]
The marriage between Mowbray E. H. Charrington and Nancy E. Green is the only one between individuals of those surnames in U.K. records for over a hundred years; accordingly, the births of Nicholas R. Charrington in 1952, Nicholas H. Charrington in 1953, and Simon M. L. Charrington in 1956 can reasonably be attributed to these parents. [N.b.- all three were born in Gloucestershire, the first Nicholas at Bristol, the second and S. M. L. Charrington at Cheltenham. I checked for a death record for a Nicholas R. Charrington, but none was apparent; I can only conclude there was some duplication of the birth record, or something of that order.]
A Nicholas H. Charrington m. 1980, Rosemary A. Hanks; this is presumably the Rosemary Charrington involved with the Pony Racing Authority, appearing in related results as resident at Glenbrook. Company records give a Simon Leonard Mowbray Charrington, b. 1956, chartered accountant, very likely the Simon as above.
The only thing that's now making me think twice is that if Mowbray Edwin Hugh Charrington and Nancy had issue (which, based on their marriage being the only Charrington/ Green marriage that's a possibility, and given the births of the above-mentioned Charrington children etc, I'm fairly sure is the case), why does Pippa Charrington's obituary not reference her own children? And yet, it's a fact that the marriage record for John Arthur Pepys Charrington gives his wife's name as 'Nancy E. D. Charrington', and another fact that the Nancy E. Green of whom you've informed me is the only likely contender that would make all the above make sense; simply taking into account the Telegraph obituary, though, my instinct would be to conclude that 'Pippa' isn't the same as the Nancy E. Green who married Mowbray E. H. Charrington, only because of the aforementioned lack of mention of her own children. This is turning out to be quite the conundrum!