AMBER ROSE finally popped that kid out yesterday.   Fiancé WIZ KHALIFA Tweeted, "Happy Birthday Sebastian 'The Bash' Taylor Thomaz!!! Everyone welcome this perfect young man into the world." (Wiz Khalifa's real name is Cameron Jibril Thomaz.)

Wiz was apparently in the delivery room with Amber, because he also Tweeted a picture of himself in hospital garb, along with the caption "Daddy Time". Check it out here.