Amber Rose and Wiz Khalifa are having a baby boy.

The model - who is expecting her first child with her fiance - accidentally revealed the sex of their forthcoming child on social networking site Twitter in a tweet thanking one of her friends for purchasing an all in one sleepsuit decorated with a picture of Guns N' Roses guitarist Slash for their baby.

"My friend Maria bought our Lil Boy this Slash onesie..... Oops did I say Lil Boy??? 😉 (sic)" she wrote.

It is not known whether the 29-year-old beauty - who is in her second trimester - genuinely meant to reveal whether she is having a boy or a girl, but earlier this month the "Black and Yellow" hitmaker refused to say whether the couple are having a son or a daughter: "I do know, but then [Amber] told us not to say yet. We'll wait until she's ready."

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