The animator who refined the look for Bugs Bunny that brought laughter to millions of people has died. Robert “Bob” Givens was 99 and died of acute respiratory failure, according to his daughter, Mariana Givens.

Givens spent 60 years as an animator during Hollywood’s golden era of cartooning, working for the Walt Disney Co., Warner Bros. and Hanna-Barbera. In addition to Bugs Bunny, he drew such characters as Daffy Duck, Tom & Jerry, Popeye and Alvin & The Chipmunks.

The genesis of Bugs Bunny’s redesign began with a conversation with director Tex Avery. The original sketches of the character “looked like Daffy Duck,” said Mariana Givens, and was deemed “too cute” for the type of mischief that rascally rabbit Bugs would concoct.

Givens went to work and came up with the first official design for the Looney Tunes character, who became one of the most recognizable cartoon characters in the world.

In 1937, Givens began his career at Disney, working on Donald Duck and Snow White, then joined Warner Bros in 1940, becoming famous for his Bugs Bunny work.

His career was then interrupted by World War II service. Upon his return, he became a storyboard artist on the TV series Linus! The Lion Hearted and later worked as a graphic designer on the show Baggy Pants & the Nitwits.

He is survived by his daughter, Mariana, who serves as president of Platinum Pathways; a son, Christopher; a grandson, Sam Givens; step granddaughters Karen Pingipore and Paula Santangelo; and many great grandchildren, nieces and nephews. The Animation Guild will memorialize him in a special program scheduled for Feb. 10, according to Mariana Givens.