The Bridesmaids star, who didn't acknowledge her first pregnancy publicly, has spoken to Jones magazine - David Jones' new fashion publication - about the upcoming addition to her family.

"I'm a little tired but feeling good ... You always get a little bit more attention when you're pregnant, which is fabulous," she said.

Byrne and her partner, fellow actor Bobby Cannavale, announced the news of Rocco's birth when Cannavale appeared on The Late Show with Stephen Colbert early last year.

Byrne and Cannavale began dating in 2012 and have co-starred in films Adult Beginners, Annie and Spy.

She worked throughout her first pregnancy, filming Bad Neighbours 2 alongside Seth Rogen. The script was tailored to accommodate her need to scale back physical comedy.

Her latest project is a little more low key.

Together with Margot Robbie and Elizabeth Debicki she is working on a new children's movie, an animated feature based on Peter Rabbit.

"I really enjoyed working through my pregnancy. Everyone was very nice to me. So I plan to do it on every job. Wish me luck," she said last year.

As well as acting, Byrne is also one of the founding members of Dollhouse Pictures, a creative collective and independent production company based in Sydney.

While she was coy about divulging further details of her private life she spoke of what she envisages her children doing in the future.

"I remember doing the film The Rage in Placid Lake years ago with Ben Lee, about the kid who rebelled against his bohemian parents and became an accountant," she said. "Maybe my kids will want to do something really different, like run a granola company or become accountants themselves."