PIC: Chris Hemsworth Rubs Elsa Pataky's Baby Bump at Avengers Premiere

PIC: Chris Hemsworth Rubs Elsa Pataky's Baby Bump at Avengers Premiere

Chris Hemsworth and Elsa Pataky only have a few more months before they become first-time parents.

The Australian actor, 28, and his Spanish wife, 35, hit up The Avengers premiere in London Thursday, where Pataky showed off her growing baby bump in an emerald Hoss Intropia gown. Hemsworth (in a Calvin Klein suit) lovingly rubbed his wife's belly on the red carpet.

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"She's so proud of Chris and he's proud of her," a source tells Us Weekly of the couple, who wed in December 2010. "They are an adorable family already!"

Hemsworth plays Thor in The Avengers alongside Chris Evans, 30, Scarlett Johansson, 27, Samuel L. Jackson, 63, Robert Downey Jr., 47, Mark Ruffalo, 44, and Jeremy Renner, 41.

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"Much like these characters, they're surrounded by bravado but underneath there's insecurity and self doubt," Hemsworth told Us at the London premiere. "That's how I felt on the first day, walking on the set -- rather intimidated!"

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Hemsworth eventually got over his nerves, and he's quite proud of the finished product. "If you want to be entertained then this delivers," the actor promised. "It's a great, humorous. . . big movie."

This article originally appeared on Usmagazine.com: PIC: Chris Hemsworth Rubs Elsa Pataky's Baby Bump at Avengers Premiere