"That is really exciting news that Katherine now, you know, be pregnant and have a baby -- I don't know when exactly. Sometime this summer," he said. "And, inevitably, I'm really looking forward to playing around with whatever it is, she or he, and have some fun."
Schwarzenegger pointed out the unborn baby's impressive lineage. The child will be part Schwarzenegger, part Pratt and part Kennedy, as Katherine is the daughter of Maria Shriver, whose mother was the sister of president John F. Kennedy.
"I mean, we can do anything. We can go and solve the Cuban missile crisis, we can go and kill Predators with our bare hands and we go and train dinosaurs," Schwarzenegger said, referencing his role in Predator and Pratt's role in Jurassic World. "I mean, think about this. That is a lot of power here."
Schwarzenegger jokingly added that he hopes the baby doesn't inherit his strong Austrian accent.
"Worst thing is if this kid ends up, you know, with my accent," he said. "That's what we don't want."
News broke in April that Katherine and Pratt are expecting. The couple will celebrate their first wedding anniversary June 8.
"Chris and Katherine are so happy," a source told People. "They wanted to enjoy this time privately for as long as possible, but now that Katherine is showing more, they're excited to share the news with everyone."
Pratt plays Owen Grady in the Jurassic World films and Peter Quill, aka Star-Lord, in the Guardians of the Galaxy movies. Katherine has published multiple books, including The Gift of Forgiveness, released in March.