"The truth is the truth and it IS needed for healing after 15 years," Marcil said.
Earlier this week, the "General Hospital" star claimed Green had cut Kassius, 16, out of his life half a decade ago as he moved on with his new family with Megan Fox.
But on Tuesday, Marcil clarified her statements in another Instagram post, admitting her baby daddy had seen his son at a few social gatherings and for brief lunches.
"They have been at the same wedding, same resort, and same play a few times in passing and a few 60 minute lunches," Marcil replied to the fan. "That is it."
"From yesterday also so calm tf down guys," she captioned the screenshot. "The truth is the truth and it IS needed for healing after 15 years. Love to all parents. Moms and dads. Let's put our kids first."
TooFab has contacted representatives for Green and Fox regarding Marcil's claims.
Green welcomed Kassius in 2002 with Marcil, who he co-starred in "Beverly Hills, 90210" with from 1998 to 2000. Following their split, Green went on to marry Fox in 2010, who he now shares three sons with -- Noah, 6, Bodhi, 4, and Journey, 2.
Marcil first spoke publicly about the issue on Monday in a lengthy Instagram caption.
"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. They lost that case & a civil case asking me for 200,000," Marcil's post began.
"I never spoke publicly in order to protect my then young son from paparazzi that used to follow him & terrify him. 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," she continued.
"Then, 5 years ago on their own they decided to completely cut Kass out of their lives and his younger brothers' lives," Marcil alleged. "Kass has never met his youngest brother and is not allowed to know where his bio father, stepmother and three younger brothers live. 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. Let's do better for our kids. Let's share our stories. #Buddhakids".
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