(Steve Granitz/Getty Images)

It's a boy for Wiz Khalifa and Amber Rose!

The rapper and his fiance welcomed their first child, Sebastian 'The Bash' Taylor Thomaz, into the world Thursday.

"Happy Birthday Sebastian 'The Bash' Taylor Thomaz!!! Everyone welcome this perfect young man into the world," the rapper tweeted.

"Happy Birthday to our baby boy Sebastian "The Bash" Taylor Thomaz! I'm so happy u guys I fell in love all over again! :-)" the model tweeted.

It appears the Wiz is off to a good start as a father. Rose tweeted a photo of the rapper holding their little boy with the caption, "Best daddy ever…. Up with the baby so Muva [Rose's nickname] can go back to sleep :-)."

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Rihanna and Snoop Dogg both tweeted their congratulations to the happy parents.

"Congratulations to my fam @mistercap and @muvarosebud !!! Welcome baby Bash! You're born in an exquisite month #babypisces," she tweeted with a photo of her and Rose.

"Welcome 2 fatherhood mistercap!!! Congrats 2 u n @darealamberrose on ur new son," Snoop Dogg tweeted.

In an interview with E! News in December, Khalifa said he's not making any changes to his marijuana use despite their baby boy.

"I think it's all about how you're raised with it," the rapper said. "Before, there was a much more negative outtake on it. You know, pot and what it can do, and the effects of it.

"Of course I'm not going to be smoking right there over the baby, because smoke in general and being high is not good for a kid. None of that," he said. "But definitely he's going to know what it is - and he'll know the difference between being a child and not being able to use it and being an adult and knowing how to use it."

SEE MORE: Wiz Khalifa, Amber Rose: 'Our Son Is Just Going to Know That Daddy Likes to Smoke'