Post Malone and his fiancée have welcomed their first child.

The Circles rapper revealed during an appearance on SiriusXM's The Howard Stern Show on Monday that he was engaged to his girlfriend - whom he has not publicly named - and is father to a baby girl.

Post, real name Austin Post, subtly shared the news as he discussed his songwriting process and recording schedule, saying that he "kissed" his "baby girl" before recently heading to the studio.

Stern then asked if he was referring to his girlfriend or a baby and Post replied, "That's my daughter."

"That's been on the QT (quiet) though? We didn't know you had a daughter, right? You keep all that quiet," Stern asked the musician, who explained, "Yeah, I want to let her make her own decisions."

Elsewhere in the conversation, Stern asked if Post's partner was his girlfriend or wife, and he simply stated, "Fiancée".

The 26-year-old did not reveal when he got engaged or when their baby was born.

The news comes just over a month after the rapper confirmed he was going to be a father.

"I'm excited for this next chapter in my life," he said in a statement to multiple outlets. "I'm the happiest I've ever been, and for since I could remember I was sad. Time to take care of my body and my family and friends, and spread as much love as we can every day."