"Ryan Sweeting is a great guy and I know he's going to take great care of her," Kunal Nayyar, 32, told PEOPLE on the red carpet at Sunday night's Golden Globes.
Nayyar, who called the New Year's Eve nuptials "a really, really great night," felt honored to be a part of the experience.
"We're a family," he said of his cast. "Kaley is like a sister to me. You become so close over such a long period of time. It's like your family member getting married."
Cuoco, 28, has been quite vocal about her fondness for Sweeting, 26. And it seems Nayyar sees why she feels the way she does.
"I think they both complement each other really well," he said. "I think the beauty of their relationship is they don't take anything too seriously. They're always laughing, which is really important in a marriage. Hopefully they'll keep each other in check."
And as for falling so hard, so fast? The actor says simply, "You know what? Love is love. There are no rules when it comes to marriage and love."