Robert Sherman, who composed classic Disney songs such as Supercalifragilisticexpialidocious and It's a Small World (After All), has died in London at the age of 86.
With his brother Richard, the late musician wrote songs for films such as Mary Poppins, Chitty Chitty Bang Bang and The Jungle Book.
His death, on Monday, was announced by his son Jeffrey Sherman with a message on Facebook and confirmed by his agent Stella Richards.
"I have very sad news to convey," his son said.
"My Dad, Robert Sherman, passed away ... in London. He went peacefully after months of truly valiantly fending off death.
"He loved life and his dear heart finally slowed to a stop when he could fight no more."
The Sherman brothers won two Academy Awards, for Mary Poppins, including best song for Chim Chim Cher-ee.
They were nominated for several more Oscars, including for the title song from Chitty Chitty Bang Bang, during their career, which spanned more than 50 years.
They were honoured with a star on the Hollywood Walk Of Fame in 1976.
The brothers enjoyed a 10-year association with Walt Disney in which they composed more than 150 songs for films, TV shows and Disneyland.
Their most famous compositions include A Spoonful Of Sugar in Mary Poppins, Trust In Me and I Wanna Be Like You from The Jungle Book, and Truly Scrumptious and Me Ol' Bamboo from Chitty Chitty Bang Bang.
Their other Disney credits include the Winnie The Pooh series, Bedknobs And Broomsticks, The Sword In The Stone, The Aristocats and The Happiest Millionaire.
Jeffrey wrote on his Facebook page: "I will write more about this incredible man I love and admire so much when I am better rested and composed. He deserves that.
"In the meantime, please say a prayer for him. As he said, he wanted to bring happiness to the world and, unquestionably, he succeeded.
"His love and his prayers, his philosophy and his poetry will live on forever. Forever his songs and his genius will bring hope, joy and love to this small, small world.
"I love you, Dad. Safe travels."