Anthony Trollope - Duke's Children

In the last of the six Palliser novels, the sudden death of his wife, Lady Glencora, leaves Plantagenet Palliser, the Duke of Omnium, finding himself in charge of his three children. The eldest, Lord Silverbridge, has recently been expelled from Oxford; his younger brother, Gerald, is about to enter Cambridge; and the youngest, nineteen-year old Lady Mary, has imprudently formed an attachment to Francis Tregear, who, while certainly a gentleman, unfortunately has no income. Before her death, Glencora knew (and approved) of her daughter's attachment; the Duke, however, does not know of it, and is not at all likely to approve. Mrs. Finn (the former Marie Goesler), who was Glencora's closest friend, learns from Mary of her love for Tregear, and is faced with the question of either keeping silent, thus breaking faith with the Duke (who has entrusted Lady Mary to her care) or telling the Duke, and breaking faith with Mary herself.
Somewhat later Lord Silverbridge himself forms an attachment to an unsuitable (because American!) girl. The Duke, whose overriding passions in life are politics and the decimalization of English currency, finds himself facing the problems brought by his children, which now have to be resolved without their mother's help. It is, in short, a novel about the generation gap, and though Trollope would never have used the term, he was obviously familiar with the problem.
(Summary Nicholas Clifford)

The other Palliser novels are
1 — Can You Forgive Her?
2 — Phineas Finn, the Irish Member
3 — The Eustace Diamonds
4 — Phineus Redux
5 — The Prime Minister
6 — The Duke's Children