The 29-year-old gave birth "a few weeks ago" but the notoriously private couple have been keeping mum on the details, News Ltd papers reported.

"I'm just excited that Rocket gets a sibling and that they'll be so close [in age] together," Lara told Instyle magazine in June.

Rocket Zot was born in LA in March 2015. 

"I'm sure it might seem full-on at the beginning for me, and it's probably a lot harder than it is now, but when they get older they can share their life together," she said.

In the interview, the Cronulla-born, New York-living former model said that leading up to the birth she would be going "into recluse mode again"

While she said in the past she would like to have four children, she said she was reassessing that number.

"Since having Rocket, maybe not four… it is life changing," she laughed.

The former reality TV star runs her online business The Base from their New York apartment. Sam Worthington, 40, who was photographed taking Rocket to a store in New York, is due to begin filming Avatar 2 at the end of the year in LA.

Fairfax Media

First appeared in the SMH