With razor-sharp wit, Mitford blends a comedy of manners with culture shock as Grace Allingham, a naive English rose, marries Charles-Edouard de Valhubert, a French aristo who doesn't believe in fidelity. Both are duped, meantime, by their son Sigismund -- the Blessing of the title -- a juvenile Machiavelli who mixes Gallic cunning with Saxon thoroughness to become one of Mitford's most memorable characters.