Ryan and Sandy!

Sandra Bullock and Ryan Reynolds are getting back to nature.

The friends and former co-stars were spotted on a hike with Sandra's son, Louis, over the weekend in photos posted on TMZ.

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The stars and other friends trekked the trails in Grand Teton National Park in Wyoming.
Ryan is seen carrying Sandra's son in a backpack carrier.

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According to Us Weekly, "The Proposal" co-stars are not romantically involved.

"They're very close and talk together a lot," a source close to Ryan told the mag. "It would make sense for them to pair up romantically, but for now, they're just friends."

Both Sandra and Ryan ended their respective marriages in 2010.
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Check out the duo and baby Louis on a hike, HERE!

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