John Farnham marks 77th birthday with touching family photo as music legend continues cancer recovery after revealing he'll never perform again

celebrated his 77th birthday surrounded by those closest to him on Wednesday, with his family sharing a rare glimpse as he continues his recovery from oral .

The heartwarming image, posted by his son James Farnham, showed the legendary singer beaming as he cuddled his one-year-old grandson Jett while celebrating the milestone.

'Happy Birthday Grandpa! We love you so much,' James wrote alongside the touching snap.

'Thank you for everything and being who you are.'

The post delighted fans, offering an uncommon look at Farnham, who has largely stayed out of the public eye since undergoing extensive cancer treatment.

The birthday celebration comes just weeks after the You're hitmaker confirmed the heartbreaking news that he will never return to the concert stage.

Speaking earlier this year, Farnham admitted the lasting effects of multiple surgeries to his mouth and jaw had made impossible.

'We can rule that out,' he said.

'Because of the surgeries to my mouth and face over the past few years, singing on stage is not something I can consider again. It's just not possible.'

Despite stepping away from live performances, Farnham remains at the centre of a major tribute concert celebrating his extraordinary career while .

The Songs of John Farnham: A Living Legend - The Celebration Concert will take place at Melbourne's Rod Laver Arena on September 20, with proceeds .

The star-studded event will feature performances from an impressive line-up including Celine Dion, Hugh Jackman, Keith Urban, Tina Arena, Jimmy Barnes, Mahalia Barnes, Richard Marx, Kate Ceberano, Human Nature, Jessica Mauboy, Jon Stevens, Diesel, Mitch Tambo, Jack Jones, Mark Vincent, Ross Wilson, Hans and Ruby Rodgers.

Demand for the event has been overwhelming, with tickets selling out within hours of going on sale.

Farnham initially resisted the idea of a tribute concert before changing his mind when organisers explained it would help raise funds for Australians battling head and neck cancers.

The beloved entertainer has described the support from fellow artists as 'truly humbling'.