The Birds on the Trees is a novel by Nina Bawden first published in 1970 about a middle-class English family whose 19-year-old son does not live up to his parents' expectations.
[1] Toby Flower is a shy, reticent youth who has grown his hair long and who has started wearing a burnous.
His father, an editor, and his mother, a novelist, are thrown into despair when Toby is expelled from school because he has been taking drugs.
Toby eventually breaks out of that stifling atmosphere, leaves home and moves to London, where he lives in a basement flat without keeping in touch with his parents.
Charlie and Maggie Flower finally turn to a psychiatrist friend of theirs who agrees to have Toby hospitalised and treated for mental illness.