Speaking on a special edition of James Corden's Carpool Karaoke, the Canadian crooner became emotional when talking about the now five-year-old Noah's battle with cancer in 2016. However, towards the end of their time together, Corden asked Buble about his son, the cancer diagnosis, and what it was like to watch your young child go through something so terrible.
"I think any person really, but particularly any parent of young children, essentially what I think you've gone through in the last few years is everybody's worst nightmare. Obviously we got his diagnosis and that was it, my whole life ended", he said.
The Grammy victor was visibly shaken saying, "It's too hard to talk about, man ... basically they said that it wasn't great. God, thank you Jesus Christ".
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Buble admitted the ordeal of watching his eldest son suffer through liver cancer was more than he could take, revealing he was "not OK".
"It's amusing, I know he's 5 years old and I say to him - because he loves Spider-Man, we love Spider-Man - and I always say to him, 'Spider-Man's wonderful, Superman's incredible, but they're fake". My wife picks me up.
The great news in this clip is that Buble's son seems to be in remission, with Buble explaining that doctors told the family "We did it [successfully removed the cancer], he's good, he's okay". "They're not real. You're a superhero, you're my hero". "I don't talk about the whole story, not even to my friends because it hurts too much", he said in an interview in July. Many times I wish that it had been.