Brian Austin Green and Machine Gun Kelly's feud heats up over Megan Fox baby drama

Brian Austin Green is not holding back after Machine Gun Kelly slid into his DMs with a fiery message.

The 90210 alum, 51, took to his Instagram Stories on Wednesday to share a screenshot of a private message from Machine Gun Kelly — real name Colson Baker — who scolded Green for allegedly pestering about when his baby with Megan Fox, 38, is due.

"Stop asking when our child is gonna be born. You the FEDS," Kelly, 34, wrote. "Quit calling TMZ and focus on that apology you owe me for speaking my name in public."

But that wasn’t all. Kelly went on to add a stinging remark: "You chose the wrong one to [expletive] with, Mr. Child Actor. Go back to cereal commercials."

Green, who shares three children — Noah Shannon, 12, Bodhi Ransom, 10, and Journey River, 8 — with his ex-wife Fox, didn’t take kindly to Kelly’s aggressive tone.

Posting the DM exchange on his Instagram Stories, Green clapped back with a sarcastic response: "I didn’t know 'child actor' was something bad."

Taking it a step further, he added: "Leo, careful," referring to Hollywood superstar Leonardo DiCaprio, known for starting his career as a child actor on Growing Pains.

"He may be coming for you next."

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