Michael Buble left viewers absolutely heartbroken as he detailed the liver cancer diagnosis of his five-year-old son Noah.
The Canadian singer, 43, enjoyed a singalong with James Corden for a Carpool Karaoke special during Stand Up To Cancer UK on Friday night, when talked turned serious as he confessed "his whole world ended" upon learning of Noah's diagnosis at the tender age of 3, according to the Daily Mail.
The hitmaker stated that despite "not being OK" he had to "somehow pull his family together and be positive' - but when he learnt his son was officially cancer-free he 'fell and his wife Luisana Lopilato picks him up now."
Speaking candidly to James about the heartbreaking situation, Michael explained: "It is so hard to have to acknowledge it. Obviously we got his diagnosis and that was it, my whole life ended."
"At first it was just, it is too hard to talk about. They said it wasn't great so we took it day by day," Michael emotionally revealed, before adding: "We had the best doctors."
Michael went on to confess: "I wasn't OK. When this all started I became the strength to somehow pull us and lift us. When they got it out and chemo was done, I just fell. My wife picks me up."
The Feeling Good singer fondly recalled: "He is five years old now and I say to him Spiderman is amazing but they are fake, they are not real. You are my hero, you are my superhero."
Michael's candid confessions left James, who is a father to three, completely emotional and the pair embraced at the end of the segment.
The pals also went on to execute passionate renditions of Haven't Met You Yet as well as It's A Beautiful Day.
Michael, who is set to release his new album Love in November, sang his heart out alongside the Late Late Show host for the charity special which is close to his heart.
Earlier this month Michael explained that the heartache he endured following his son's cancer diagnosis at just three years old changed his 'perception of life', as he admitted that he is now done with fame.
Noah, now five, is currently in remission following his battle with liver cancer, but the ordeal has been life-changing for Bublé, who has since questioned his career in showbusiness.
Michael is married to Argentinian actress Luisana Lopilato, 31, and they share three children together; their eldest son Noah, son Elias, two, and daughter Vida, whom they welcomed two months ago.
Both he and Luisana put their careers on hold to be there for their son - they jetted to the US so Noah could undergo treatment for hepatoblastoma.
Speaking in what he claimed to be his 'last interview' with Daily Mail's Weekend magazine earlier this month, he admitted: 'It's been such a difficult exercise. It hurts me, and it hurts to talk about Noah because it's not my story to tell, it's his.
"But my whole being's changed. My perception of life. I don't know if I can even get through this conversation without crying. And I've never lost control of my emotions in public.
"I actually thought I'd never come back to the music business. I never fell out of love with music, I just needed to put it aside.
"What was hard was going to the store to buy hot dogs and toilet paper, going to the gas station. Going for a walk by the sea to clear my head.
"Everyone recognises me and says, 'How's your son?' When you think you're close to getting over it you're sucked right back into it. But at the same time I was given faith in humanity.
"The media helped me, they weren't disrespectful. And in those two years my record company never asked me what the plan was. They said, 'We love you and we're praying for you.'"
But he also admitted: "I'd lost the joy and at some point just before the Brits I was starting to lose the plot. I'd become desperate to hold onto something I thought I might be losing, and I thought I had to do something special to keep it.
"I'd started to do things out of my comfort zone, like presenting, and the truth is it had been a while since I'd been having fun. I'd started to worry about ticket sales for my tours, what the critics said, what the perception of me might be."
"But the diagnosis made me realise how stupid I'd been to worry about these unimportant things. I was embarrassed by my ego, that it had allowed this insecurity.
"And I decided I'd never read my name again in print, never read a review, and I never have. I decided I'd never use social media again, and I never have."
Michael's album Love will be released on 16 November. Click here to make a donation to Stand Up To Cancer.