The Young Money family just got younger, as rapper Tyga and his model girlfriend Blac Chyna announce the birth of their son, King Cairo Stevenson.

The baby boy was born earlier today in Los Angeles, weighing 7 pounds, 1 ounce.

"Most Amazing feeling ever," the 22-year-old "Rack City" MC tweeted, along with a photo of himself cradling his newborn son.

"Welcome King Cairo Stevenson 7lbs 1 oz ....... #blessed !!!!" Blac Chyna wrote. "40 long weeks .... So happy words can't explain !!!"

Blac Chyna, who starred in the "Rack City" video, Tyga and King Cairo will reside together in their recently purchased $6.5 million mansion in Calabasas, Calif. Though the couple were rumored to have gotten engaged earlier this year, Tyga denied the reports.

Tyga will hit the road later this month, opening for Nicki Minaj.

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