Sources with direct knowledge tell us the baby arrived August 3rd in Los Angeles. We don't yet know the kiddo's name, but we do know it starts with "R" and it's a boy.
The last time we saw Rihanna was back in June, when she and Rocky were globetrotting, she looked far along in her pregnancy at that time.
Remember ... Rihanna announced her second pregnancy back in February, during her Super Bowl halftime show. RiRi was rocking an obvious baby bump for the huge surprise, shocking viewers all around the globe.
So the latest development officially makes RZA a big brother.
As we reported ... RiRi went topless during a maternity photo shoot for her first pregnancy, though she didn't share the photos until a few days after RZA's first birthday.
When she posted the pics, Rihanna hinted at a second topless maternity shoot because she included a #tobecontinued hashtag on her post ... so it will be interesting to see if she follows through.
Congrats to the whole family!!!
We covered the story in the latest episode of The TMZ Podcast, available on all podcast platforms.