According to Yes Dawn French

Dawn French, number one bestselling author of A Tiny Bit Marvellous and Oh Dear Silvia, returns with her joyously funny new novel, According To YES.
The Foreign Land of the Very Wealthy - otherwise known as Manhattans Upper East Side - has its own rigid code of behaviour. Its a code strictly adhered to by the Wilder-Bingham family.
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Emotional displays - unacceptable. Unruly behaviour - definitely not welcome. Fun - no thanks. This is Glenn Wilder-Binghams kingdom. A beautifully displayed impeccably edited fortress of restraint.

So when Rosie Kitto, an eccentric thirty-eight-year-old primary school teacher from England, bounces into their lives with a secret sorrow and a heart as big as the city, nobody realises that she hasnt read the rule book.
For the Wilder-Bingham family, whose lives begin to unravel thread by thread, the consequences are explosive. Because after a lifetime of saying no, what happens when everyone starts saying . . . yes?