Chris Pratt Says Arnold Schwarzenegger's Support 'Means the World': 'Really Kind of Mind-Blowing' (Exclusive)

Chris Pratt feels nothing but support from his father-in-law Arnold Schwarzenegger.

Before a special screening of Guardians of the Galaxy Vol. 3 at the IPIC Theater Fulton Market in New York City on Wednesday, Pratt opened up to PEOPLE about his relationship with the Terminator star.

"Arnold's support means the world to me on a couple different levels. Just being his son-in-law and being part of his family, it obviously means a lot to have his support," began Pratt, 43.

"But then on another level, just being somebody who grew up loving his movies, the big action hero — I dreamed of being Commando and dreamed of being the soldier from Predator, and I loved Terminator," he added. "So him to give me kudos for going out and being on the marquee is really kind of mind-blowing."

Schwarzenegger, 75, congratulated his son-in-law on his new Marvel film, writing on Twitter Friday that he "crushed" his latest performance as Star-Lord.

"I saw #GuardiansOfTheGalaxyVol3 last night and WOW," Schwarzenegger wrote. "@prattprattpratt, you crushed it. A non-stop, perfect mix of comedy and action. I loved it and I'm very, very proud of you."

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Pratt described how he's changed after 10 years of playing his character to PEOPLE. "The heart of this character, the soul of this character, has always been mine," Pratt said. "That divine spark that is in me is also in this character."

He continued, "His different set of life experiences and the circumstances that created him make him different than me, and in the past 10 years, the circumstances that have created me make me different than who I was 10 years ago in that way."

"So I'm not sure it was so much Star-Lord that changed me — although being cast as Star-Lord has certainly had a profound impact on me and how I manage day to day. And how my grandchildren will be able to go to college," he joked.

Pratt is married to and shares two children — daughters Lyla Maria, 2, and 11-month-old Eloise Christina — with Arnold's daughter, Katherine Schwarzenegger. He is also a dad to 10-year-old son Jack, whom he shares with ex-wife Anna Faris.

As for which of her husband's films is her personal favorite, Pratt told PEOPLE, "Her favorite movie is Bride Wars. Katherine is a huge fan of Bride Wars. She calls that 'true cinema.' And I think that might be one of the only movies of mine she's seen."

Pratt played Anne Hathaway's romantic interest in the 2009 comedy, which stars Hathaway and Kate Hudson as best friends fighting to have their dream wedding on the same day.