Michael Buble and Luisana Lopilato "had doubts" on their wedding day about getting married.

Luisana Lopilato and Michael Buble married in 2011

Luisana Lopilato and Michael Buble married in 2011

The couple - who are expecting their fourth child together - tied the knot in 2011 and although they have a "beautiful" relationship, they admitted their paths could have been very different.

The 'Home' singer said: “It’s the most beautiful, beautiful thing. You know, this could have turned out another way. The day we got married, I think we both had huge doubts. We both were, like: ‘Oh wow, really, who is this person?’

“I don’t think it was any different than any other marriage. Maybe we were less ready than other marriages."

After the ceremony, they both felt like they had made a "big mistake" in getting hitched.

Michael continued: "Even on our honeymoon, I remember you were like: ‘I think we made a mistake.’ And I was like: ‘You know, I think you’re right. We did make a mistake.’”

Luisana recalled to Britain's HELLO! magazine: “I was expecting for him to tell me: ‘Oh no, don’t worry,’ but he said to me: ‘I think so, too. I think we made a big mistake. And I was, like [ loud gasp] and then he said to me…”

Michael even told his new wife it was "not too late to annul the marriage".

Fortunately, the loved-up pair - who already parents to Noah, eight, Elias, six, and Vida, three - fought for their marriage and have only grown fonder of each other.

Luisana: “We stepped back, took an adult decision and said: ‘We have to try harder.’

“I think I love him more than when I got married, for sure. I think our life got better, and our relationship. I can be transparent with Mike all the time and tell him all the things I don’t like, and tell him what I like. I feel that we are good to each other.”