Lil Bub, one of the internet’s most famous cats, has died aged eight, reports BBC.
Mr Bridavsky said she helped raise more than $700,000 (£540,000) for animal charities during her lifetime.
“Bub has made a huge difference in the world of animal welfare, and in the lives of millions of people worldwide,” a post on Instagram said.
Lil Bub found online fame because of her unique appearance. Her feline dwarfism meant she stayed kitten-sized throughout her life.
She was also polydactyl, with an extra toe on each paw, and had an underdeveloped jaw and no teeth which caused her tongue to always hang out.