Liam Neeson Shares His Greatest Fear as a Single Dad

March 27, 2014 -- Like every parent, Liam Neeson can't help but worry about his two sons.

Four years after losing his wife in a skiing accident, the "Taken" star added that he knows the onus is on him to keep them in line.

"My boys are teenagers. They're experimenting. They're flexing muscles and sometimes dangerous avenues, and you think, 'F***. If Tasha was here, someone could share this.'" he told GQ magazine for their cover story. "But yeah, we're doing all right, you know?"

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Neeson, 61, said that one of most important lessons he's instilled in his sons Micheál, 18, and Daniel, 17, is the importance of manners. Neeson added that adults often compliment him on how respectful they are, though he said that he still worries about his sons acting out.

"There's a worry nowadays, with every parent I've spoken to. It's f***ing drugs. It's a virus," he said. "A teenager can take it and suddenly they can be hooked, and it changes their life and their family's forever. That's my constant worry. And I trust them, and they're sensible boys, but it can be just that chemistry that doesn't work."

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While Neeson said that he was "never into drugs," he recalled a time in 2000 when he was given morphine after a motorcycle accident and got "hooked."

Now, however, he said that he doesn't even drink anymore.

"I was just—I was drinking too much. It started since my wife died," he said, adding that he only drank Pinot Noir wine and, for awhile, Guinness, though he gave that up awhile ago for health reasons. "So last year, I just thought—they've been throwing these action movies at me, and I thought, 'Okay, let's just change it a little bit.' And it's been great. I love it."