Mel B was convinced the royal baby would be a girl.
Prince William and Duchess Catherine welcomed their son - the third-in-line to the British throne after his father - into the world at 4:24pm on Monday afternoon (22.07.13) and the tot weighed 8lbs 6oz.
The former Spice Girl is very excited about the birth of the couple's son, but she thought they were having a little princess.
Speaking on 'The Kyle & Jackie O Show' on Australian radio station 2Day FM, she said: "I'm so excited, I too was convinced it was going to be a girl, they did a poll and it ridiculous, something like 73 per cent of people though it was going to be a girl."
Mel B is currently in the US filming 'America's Got Talent' and she has been surprised at the jubilant reaction to the baby news in America.
She added: "It's gone nuts and it's gone even more nuts over here in the States, people are so excited it's quite funny. This is a big one, this is a real big one. I'm so glad finally, I was co-hosting 'The Today Show' and we were on standby."
The child is being referred to as Baby Cambridge - due to his parents' titles being the Duke and Duchess of Cambridge - until he is named by William and Catherine, but Mel believes he will be called George.
Referring to the name - the favourite amongst bookmakers - she said: "I like it, I don't mind it at all."
William and Catherine - formerly known as Kate Middleton before she got married - are expected to leave St Mary's Hospital later today and Mel B has been thinking of gifts she would give to the royal couple.
The 38-year-old star mused: "God what do you give the Royal Family as a baby present. Maybe like a piece of jewellery they can keep."
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