Brian Austin Green Praises Megan Fox While Responding to Ex's Claim She Raised Son Kassius 'Alone'

Green and ex Vanessa Marcil split in 2003.

Brian Austin Green praised Megan Fox while reacting to his ex Vanessa Marcil's claim that she raised their their son Kassius "alone."

Marcil recently held a Q&A session on her Instagram Stories and it's there where she was asked about her co-parenting situation with Green, or lack thereof. "We didn't & don't co-parent. I raised my son alone," she responded to the fan's question.

Green didn't hold back after posting a screenshot of her response. 

"So, I can’t tell you how frustrating it is to read continued lies from a 50+ year old woman on social media like she is still in high school," he fired back. "She has never in her life been someone to walk the walk. Talk is cheap. Megan and I bust our asses to give Kass a well rounded childhood since his mom was rarely there. I’m assuming that’s why she posts so much of him now. When will she just GO AWAY."

Brian Austin Green/ Instagram

Green and Marcil, who split in 2003, share now-20-year-old son Kassius. The Beverly Hills, 90210 star also shares three sons -- Noah, 10, Bodhi, 8, and Journey, 6 -- with Fox. He also recently welcomed a baby boy with Sharna Burgess.

A source told ET back in October that there's nothing but respect between Fox and Green when it comes to co-parenting. The source said Fox and Machine Gun Kelly have "blended together" with Green and Burgess.

"Megan, MGK, Brian, and Sharna are all cordial," the source shared at the time, adding that "Megan and Brian have a healthy co-parenting relationship."

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