Beloved Aussie singer John Farnham’s sons, James and Rob, have credited cancer research with helping to save their father when he battled throat cancer in 2022.

The now 76-year-old underwent a 12-hour surgery in 2022, with doctors removing a tumour from his mouth and reconstructing his jaw.

He has since been given the all-clear following the marathon operation.

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On Sunrise on Thursday, James and Ron provided a welcome update on their famous father’s health.

“He is doing good,” Rob told hosts Nat Barr and Matt “Shirvo” Shirvington.

“You know, it’s like anyone, you go through such a dramatic surgery, particularly on your face, it is going to affect you. I think he’s resilient. He’s strong.”

James added: “He’s sticking to his regimen. My mum (Jillian) makes sure he’s doing all the right things.”

The boys joked their father was stubborn, which helped in his recovery.

Rob and James have thrown their star power behind Daffodil Day to raise money for people living with cancer.

They said the charity is close to their father’s heart.

“Daffodil Day is quite important to our dad,” James said.

“He basically wouldn’t be here if it wasn’t for research and funds from events like Daffodil Day.

“So, yeah, things like this are very important. The cancer research that they do is really, really, really important to survival rates.”

Rob added: “It’s a huge thing for us and a lot of people. Daffodil Day and the Cancer Council in general does so much to support families the research.”

Hitmaker Farnham has largely stayed out of the spotlight since his cancer diagnosis.

However, he did make a rare public outing in February this year, when he was seen at Melbourne restaurant Florentino for wife Jillian’s 70th birthday.

James also spoke about how his famous father was enjoying being a first-time grandfather, after he and his partner Dr Tessa Effendi in July welcomed a baby boy, who they named Jett John Farnham.

James said rather than grandpa, his father has a shortened grandfatherly name.

“He’s called ‘Pa’. That’s what I call him,” James said.

“He likes ‘Pa’. Jett can’t say it yet but hopefully will soon.

“Dad is loving it, been hands on, (it’s) been really nice for everyone.”