A statement posted on Facebook said he died yesterday after contracting Covid-19.
It read: “It is with tremendous sadness that we announce the passing of the well known and popular Cornish comedian Jethro.
“Tragically Jethro passed away on 14th December 2021 after contracting Covid-19.
“Jethro leaves behind his life partner Jennie, sons Jesse and Lanyon, step daughter Sarah, daughter-in-law Stacey and of course his much loved grandchildren.
“We ask that you respect our privacy at this very sad time and give us all time to grieve.
“We will continue to support each other in the knowledge that our lives will never be the same without him.”
The comedy star was double jabbed and had had a booster vaccination, The Gazette understands.
Born in St Buryan in Cornwall, the stand-up’s stage name Jethro was reportedly inspired by a character of the same name from American sitcom The Beverly Hillbillies.
Throughout the 1980s he built a following in Cornwall and Devon, before making a national television performance in 1990 on the Des O’Connor Show.
In 2001, he appeared on the Royal Variety Show and went on to become one of the biggest stars from Cornwall.
In 2015, he performed alongside comic Mick Miller at the North Pier Theatre.
"When I'm in Blackpool," he said in an interview. "I flush sandwiches down the toilet to feed the birds."
In February 2020, he announced on social media he was “hanging up my mic” and retiring from the comedy circuit.
However, he promised to honour his upcoming tour dates although they were later postponed due to the onset of the coronavirus pandemic.
Comedian Jim Davidson was among the people paying tribute to him, tweeting: “My good friend Jethro has left us. RIP Jethro, you will be greatly missed.”
Comedy impressionist Danny Posthill added: “I remember when I first started showing an interest in comedy and I used to buy stand-up shows on VHS with my paper round money.
“Lee Evans, Chubby Brown, Jim Davidson, Jimmy Jones and Jethro. Sadly today one of those legends have left us. RIP Jethro. Thanks for the laughs.”
Fellow stand-up Richard Herring and Welsh tenor Paul Potts also paid tribute to the comic.