Lisa announced the news by posting a photo of herself putting her baby bump on full display while posing next to Jack.
"Literally ate the biggest burrito ever," she joked in the caption.
The lovebirds are already parents to two adorable kids, daughters Pearl, 5, and Andy Rose, 2. And judging by the pics Lisa has shared of their mini-mes on social media, we have a good feeling they will make great big sisters!
See some of our fave snaps of Pearl and Andy Rose below: