TheYoung and the Restlessstar, whodiedSunday at age 52, was last active on Twitter on Jan. 21, when he retweeted someone’s post about losing a child that reads, “Grieving the loss of a child is a process. It begins on the day your child passes, and ends the day the parent joins them.”

“Never a truer word was spoke,” St. John tweeted. “Thanks for posting this.”

According to a 2013Huffington Postprofile, Julian, an artist, was diagnosed with schizophrenia at the age of 18 and had endured bouts of severe depression since he was a child.

“Our son was the light of our lives, an artist with a beautiful mind and spirit,” said Mia, who went on to found theEl Saber es Poder (Knowledge is Power) Foundationto battle mental illness, in a statement at the time. “He fought long and hard against an illness for which there is no cure. Unfortunately, the pain became too great for him and I dare not say he lost the battle — he simply chose to set himself free. My fight for mental health will continue. They may not find a cure in my lifetime, but we can try and prevent the loss of another beautiful soul.”

Julian St. John/Facebook; Robert Voets/CBS/Getty

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The Los Angeles County Medical Examiner-Coroner confirmed to PEOPLE on Monday that St. John was found dead at a home in Woodland Hills on Sunday. He was pronounced deceased at 4:02 p.m. An autopsy is scheduled for Monday.

According to the Los Angeles Police Department, a death investigation took place at around 2:05 p.m. for a possible alcohol overdose at the 2300 block of Morea Way.TMZfirst reported the news.

Gabe Ginsberg/Getty

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The actor’s lawyer Mark Geragos addressed the news on Twitter, writing: “Few men had the unique strength, courage & sensitivity that @kristoffstjohn1 lived every single minute of every day. He impacted everyone he met and millions who he inspired and in turn admired him. On behalf of @MiaStJohnBoxer & @TheStJohnFamily thank you for all of your love.”

In 2017, St. John, who has played Neil Winters on CBS’The Young and the Restlesssince 1991, underwent psychiatric treatment after a reported scare regarding his mental health. According toTMZ, he threatened to kill himself with a gun and was placed under a 72-hour hold for psychiatric evaluation.

In a statement toEntertainment Tonightat the time, Mia blasted reports about the incident.

If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), text “home” to the Crisis Text Line at 741-741 or go to suicidepreventionlifeline.org.

source: people.com