The 65-year-old, who is the ex-wife of Rolling Stones guitarist Ronnie Wood, said she was “heartbroken” over the death of 61-year-old Paul Karslake, of Leigh-on-Sea in Essex.
A statement posted on the Instagram page of artist Mr Karslake said that he was taken to hospital with breathing problems on Sunday and died on Monday.
It described him as a “fantastic husband, a wonderful father, an amazing family man and an excellent friend to all”.
Wood paid tribute to Karslake on her Instagram account.
"This is my brother @Paulkarslakefa who died today,” she wrote.
“I love him so much I’ll miss him so much a funny talented wonderful father husband and brother ... life won’t be the same without him.”
She wrote on Twitter: "So it was COVID that took my brother's life on Monday."
Radio X presenter Gordon Smart wrote on Twitter that a painting Karslake did of Keith Richards as a pirate helped inspire Johnny Depp’s performance as Jack Sparrow in Pirates of the Caribbean.
“He was commissioned by Keef Richards many years ago to paint the Stones legend as if he was a pirate,” wrote Smart.
“It hung above the dining table in Keef’s gaff. Johnny Depp came round for dinner, clocked it - and Jack Sparrow was born x”
— Gordon Smart (@gordonsmart)March 24, 2020
There have been at least 11,658 confirmed cases of coronavirus across the UK.
Additional reporting by Press Association.