The Australian singer, who is married to Jules, yesterday confirmed that they are expecting their first child together after rumours of a pregnancy surfaced last week.
Sebastian wrote on his Twitter page: "2day we r officially out of our first trimester so it excites me 2 announce that Jules & I r expecting our first child! Cant w8 2 b parents! (sic). Thanks to all friends, family, fans etc for all your kind words. We love you."
The musician's staff were said to be furious when radio star Kyle Sandilands duped Sebastian's X Factor fellow judge Ronan Keating into confirming the rumours live on air earlier this week. Sandilands told Keating that the news was public knowledge, to which he replied: "Guy told me a while ago, I didn't realise the news was out," before realising that he had been tricked.
Friends of Sebastian have now revealed that he will not be touring until after the baby is born in March next year.
Sebastian said in an interview last year that every day is "special" for him and Jules.
He explained: "We just try to make each [day] count. There are so many ways to make your partner feel extra special. I always tell Jules how much I love her and how sexy she looks."
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Watch Guy Sebastian's video for 'Who's That Girl' below: