Two Movie Stars Made a Bet on Twitter. The Guy Who Won Just Paid Up Anyway — and When You Read the Bet You'll Understand Why.

It started with a bet between movie stars — and ended with both guys putting on their superhero costumes and visiting children's hospitals.

"Guardians of the Galaxy" star Chris Pratt and "Captain America" star Chris Evans set up a friendly wager on Twitter ahead of the 2015 Super Bowl: If Evans' favorite team, the New England Patriots, won, Pratt would visit the Christopher's Haven cancer charity in Boston dressed as Star-Lord, and if Pratt's Seattle Seahawks won, Evans would visit Seattle Children's Hospital dressed as Captain America.

Evans obviously won the bet, and Pratt visited Christopher's Haven in his superhero duds on Feb. 6.

But on Saturday, Evans decided to make as if he'd lost the bet — and he made quite a few kids in Seattle very happy.

Dressed as Captain America, Evans roamed Seattle Children's Hospital with Pratt, posing for pictures with his young fans, KING-TV reported.

The hospital tweeted some of the photos.

Meeting Captain America and Star-Lord is an experience our patients will always remember. #TwitterBowl pic.twitter.com/iDJWJ4UGbs

— Seattle Children's (@seattlechildren) March 8, 2015

A superhero size THANK YOU to @prattprattpratt & @ChrisEvans for visiting our patients today! #TwitterBowl pic.twitter.com/qgo0kKC1AV

— Seattle Children's (@seattlechildren) March 8, 2015

Evans tweeted about the day, saying he felt "inspired, blessed, touched"...

AMAZING day at @seattlechildren w @prattprattpratt. Met some TRUE super heroes! Feeling inspired, blessed, touched. Thank you w all my heart

— Chris Evans (@ChrisEvans)

March 8, 2015

...while Pratt posted about the day on Facebook.

Pratt referenced Psalm 107:19-21 in his Facebook post — here's the passage:

Then they cried to the Lord in their trouble,

and he saved them from their distress.

He sent out his word and healed them;

he rescued them from the grave.

Let them give thanks to the Lord for his unfailing love

and his wonderful deeds for mankind.

—

Follow Zach Noble (@thezachnoble) on Twitter