Megan Fox’s children are preparing to welcome their newest sibling.

While speaking to PEOPLE about her collaboration with REVOLVE, the 38-year-old actress opened up about how her sons Noah, 12, Bodhi, 10, and Journey, 8, who she shares with ex-husband Brian Austin Green, 51, are doing ) shares She announced that she is expecting her fourth baby, her first with fiancée Machine Gun Kelly, 34.

“The kids are all very excited about adding more to their family and have promised to pitch in and help out,” Fox tells PEOPLE.

Fox’s new little one joins her three sons and Kelly’s daughter Casie, 15, whom he shares with ex Emma Cannon.

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Last week, Kelly spoke out for the first time since Fox announced she was pregnant with the couple’s first child together, giving an update on his new music and noting that he’s about to become a father again.

In a post on ”

“After all, I’ll soon be a father again!” Kelly, born Colson Baker, ended his post in a friendly way.

In early November, Fox announced the couple’s exciting baby news. The Jennifer’s body In an Instagram post, the star held her baby bump while it was covered in black fluid, and in another snap, she held a positive pregnancy test up to the camera.

“Nothing is ever truly lost. Welcome back 👼🏼❤️,” she captioned the post, using lyrics from Kelly’s track “last November,” a song about his and Fox’s past pregnancy loss.

After Fox and Kelly announced they were pregnant, a source told PEOPLE that the couple “kept the baby news a secret until Megan was ready to share it,” adding that this was the case Transformers Star and musician “can’t stop talking about the baby.”

“They are very excited. He basically tells everyone he knows,” the insider said.

“Megan was nervous at the beginning of the pregnancy, but now she feels more relaxed,” the source said. “She’s trying to enjoy it. She loves being pregnant.”

The insider added that the engaged couple are “doing well” and are “focused on the baby at the moment.” He noted, “It doesn’t look like they’re getting married before the baby comes.”