The model, who announced that she was pregnant at last year's MTV Video Music Awards, gave birth to baby boy Sebastian Taylor Thomaz today (February 21).
Khalifa wrote on Twitter: "Happy Birthday Sebastian "The Bash" Taylor Thomaz!!! Everyone welcome this perfect young man into the world."
Rose had only today denied reports that she had gone into labour, tweeting: "Our Chicken nugget is still baking. :-)"
Khalifa, who was born Cameron Thomaz, revealed last year that Rose had suffered a miscarriage prior to her current pregnancy.
"I was like, 'F**k that, I want a baby'," the rapper recalled. "And she got pregnant again - like right away."
The couple got engaged to marry last year.
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