Inside Brian Austin Green and Ex Vanessa Marcil's Complicated History as She Supports Megan Fox
On Sunday, the 52-year-old actress appeared to be siding with Megan Fox after the Transformers star slammed Green for portraying her as an "absent mother."
In her post, Marcil — who has previously spoken out in support of Fox amid the star's split from Green — cryptically wrote, "Like I said... the truth always comes out in the end...," and then captioned it, "#ImWithYouSister," though she didn't mention Fox by name.
While Fox and Green share sons Noah Shannon, 8, Bodhi Ransom, 6, and Journey 4, Green is also dad to 18-year-old son Kassius Lijah, whom he shares with Marcil.
The pair first started dating in the late 1990s after meeting on the set of Beverly Hills, 90210, and got engaged in the summer of 2001. They welcomed son Kassius on March 30, 2002, though they split not long after, in 2003.
In 2018, Marcil posted an emotional message to Instagram, claiming her son had been cut out of Green and Fox's life after a lengthy and private custody battle following their split and his wedding to Fox.
“12 years ago I was served legal papers and then spent 8 years+ defending myself and my son in custody court in response to his father & his stepmother trying to get full custody (that means I would have seen my son four days a month) and then asking me to pay them child support,” Marcil wrote at the time, noting how Green lost the case, as well as a previous lawsuit for $200,000.
Despite the legal drama, Marcil said she never challenged Green’s right to 50/50 custody.
“I never spoke publicly in order to protect my then young son from paparazzi that used to follow him & terrify him,” she continued. “I had also never asked for child support of any kind and had never tried to take time away from Kass’ dad seeing him. Ever. In the end they lost all of these court cases. The judge called them all ‘Frivolous’ They always had 50% custody and still did when court ended as I had and have NEVER asked for full custody.”
According to Marcil, after Green and Fox lost the custody battle, they "decided to completely cut Kass out of their lives."
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“Kass has never met his youngest brother and is not allowed to know where his bio father, stepmother and three younger brothers live,” Marcil wrote. “Custody cases hurt the children only and the truth shall set us all free. Put the kids first you guys. There shouldn’t be a ‘more important parent’ kids love both parents equally no matter what either parent’s struggles may be.”
“Kass has been truly heartbroken since being cut out of his other families lives with NO explanation,” she concluded. “Let’s do better for our kids. Let’s share our stories.”
A rep for Green didn't respond to PEOPLE's request for comment at the time.
Since then, it seems as though Green and Fox changed their minds, as Marcil told fans in the comments of one of her post in September that she was "extremely grateful that Kass was finally invited back into his father's life."
"I was never in love with him but I am very proud of the fact that my son loves his dad unconditionally and has chosen to forgive," she wrote, referring to a comment made by a fan saying she "still loves Brian Austin Green" after the star shared a throwback photo from her pregnancy with Kassius.
"I celebrate Kassius' love for his father and remain extremely grateful that Kass was finally invited back into his father's life and was able to meet his youngest brother for the first time & finally start seeing his other two siblings again," she added. "5 years apart with no explanation is devastating for children. For siblings. My son is also an incredible & protective big brother."
And it seems as though Marcil harbors no hard feelings towards Fox over the rocky history with Green, showing her support for the actress as she navigates her split from Green and new relationship with Machine Gun Kelly.
In September, Marcil told fans during a Q&A series on Instagram that she has "respect for how [Fox] is finally living her life for herself & leaving her children out of her public life at this young age."
In fact, her most recent show of support comes after Fox called out Green in the comments section of a since deleted post for sharing an image of their youngest son on social media.
"I had a great halloween with them yesterday, and yet notice how absent they are from my social media. I know you love your kids. But I don't know why you can't stop using them to posture [sic] via Instagram," Fox wrote.
"You're so intoxicated with feeding the pervasive narrative that I'm an absent mother, and you are the perennial, eternally dedicated dad of the year. You have them half of the time," she said. "Congratulations you truly are a remarkable human! Why do you need the internet to echo back to you what should be inexhaustibly evident in the way your children love you?"
Shortly after Fox's comment, Green took down his original Halloween post. Instead, he shared the same photo but cropped out their child. "Hope you all had a happy Halloween!!!" he wrote for the revised post.