When Home Alone star Macaulay Culkin was photographed in February in New York looking scary-skinny and shockingly disheveled, it raised serious red flags about the former child star’s current health — and possibly declining mental health. But no one was more concerned about the actor’s dangerously emaciated appearance than his estranged dad, Christopher ‘Kit’ Culkin, who is secretly terrified that the 31-year-old is headed down a dark, dangerous path.

According to a source, a “totally devastated” Kit — who recently survived a risky heart transplant operation — is so distraught, he can barely talk about just how worried he is for his son. “It’s a tragic state of affairs,” reveals the source. “It’s so painful for him.”

It’s doubly painful, explains the source, because “Kit has not seen Mac since 1997” — when he was cut out of his son’s life after being fired as the then-child star’s manager, following a financial dispute. Adds the source, “Kit doesn’t want to lose another child before they’ve had a chance to mend their relationship.”

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