Despite playing a cold-hearted killing machine, Arnold Schwarzenegger proved that he’s a family man deep down when he sent a heartwarming message to a father and son fans.

A Reddit user wrote a long message on his 30th birthday Wednesday, saying that he was watching “Terminator Genisys” with his father, who first got him hooked on the franchise with “Terminator 2: Judgement Day” in 1991.

“That experience really sparked a love for film, the kind of passion that my dad had for them. From then on we saw a bunch of movies together along the years, including all the ‘Terminator’ movies until now, it was our franchise,” he wrote.

“My dad loved Arnold’s catchphrase ‘I’ll be back’ and he would just rewind it every time. I have only my dad to thank for my love for movies, it’s one of those things we always shared together.”

Also Read: 'Terminator Genisys' Review: Arnold Schwarzenegger's Swagger Can't Save This Redundant Tentpole

Tragically, in January his father — who had long suffered from mild dementia and schizophrenia — took a severe downward turn. As the Reddit user wrote, “he was hearing voices and acting very unusual, he wasn’t himself anymore … cursing and showing sign of aggression. He didn’t want to watch movies anymore and it really broke my heart seeing him this way. He was there but it felt like he just doesn’t want to partake in anything anymore.”

But miraculously watching “Terminator Genisys” brought him back to life a little. “I was actually surprised to see my dad enjoying it, not because it was this amazing film we never seen before but because for MONTHS he hasn’t smile, he used to be a very happy man and always had a big smile on his face. I know it may sound dumb but it felt like a miracle!

“Thank you /u/GovSchwarzenegger, for making my father smile again.”

Also Read: 'Terminator' for Dummies: Everything Newcomers Need to Know Before Seeing 'Genisys'

The heartwrenching message caught the attention of over 200 commentators, none of them more touched than Schwarzenegger himself, who quickly responded.

“Wow. I’m in Korea on a whirlwind tour but you stopped me in my tracks. This is so touching. Thank you for sharing. I’d like to say ‘this is why I do this’ but you should know it was you who made your father smile,” the action star wrote. “It was your presence and caring. Happy birthday, you’ve got a lot of wisdom for 30 years.”

The actor and former California governer also attached a handwritten note to the father, telling him he was happy to make him smile again — and praising what a wonderful son he had raised.

Reddit

Reddit

The writer of the original Reditt was naturally blown away by the reaction from Schwarzenegger.

“I am completely overwhelmed! So many emotions going through right now! Thank you so much/u/GovSchwarzenegger I really don’t know what to say?!” he said.

“Made me cried so much (of pure joy), we needed this. seriously, thank you from the bottom of my heart.”