"Obnoxious son"
Pomfret Towers!
by Angela Thirkell (1938)
https://angelathirkellsociety.org/writings/book-summaries/
Review Of The Year (1938)

A long weekend party affords elderly Lord and Lady Pomfret the opportunity to introduce their cousin and heir, Gillie Foster, to the gentry and incidentally (?) to eligible young ladies of the countryside.
The indefatigable Mrs. Rivers pushes her reluctant daughter, Phoebe, and, while fending off the most likely competition, self-effacing Alice Barton, she is completely outflanked by Sally Wicklow.
Sally is eminently acceptable, complementing Gillie’s retiring nature and delicate health with robust competence.
Mrs. Rivers, an outrageously successful author of formula books about middle-aged women and their not quite consummated affairs with younger men, crosses swords with Mrs. Barton who writes “learned historical novels about the more obscure bastards of Popes and Cardinals” (Renaissance era).
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