Robert B. Sherman, half of the fraternal songwriting team that wrote the ubiquitous paean to togetherness, “It’s a Small World (After All)”, and that in films like “Mary Poppins” and “Chitty Chitty Bang Bang” etched dozens of tunes and volumes of lyrics into the permanent memories of generations of children and their parents, died Tuesday in London. He was 86.

His death was confirmed by his son Jeffrey.

Mr. Sherman and his brother, Richard M. Sherman, were known for perky tunes and generally cheery lyrics, and their best-loved songs became standards of family entertainment, though their own difficult relationship was marked by decades of strain and periods of estrangement.

They won two Academy Awards — for “Chim Chim Cher-ee,” a chimney sweep’s proud anthem from “Mary Poppins,” the celebrated 1964 film about a nanny with magical powers, starring Julie Andrews and Dick Van Dyke, and for the film’s score, which included the nonsense song “Supercalifragilisticexpialidocious,” the spirited theory of child-rearing “A Spoonful of Sugar,” and “Feed the Birds,” a ballad that extols caring for other creatures, said to be a favorite of Walt Disney, their longtime boss.

The Sherman brothers worked side by side at the Disney studio from the early 1960s into the 1970s, producing songs for several movie musicals, both live-action and animated — “The Jungle Book,” “Bedknobs and Broomsticks,” “The Sword in the Stone,” “The Aristocats” and “The Happiest Millionaire” — as well as short cartoons based on A. A. Milne’s Winnie-the-Pooh stories.