Chris Pratt visits children's hospital as Guardians of the Galaxy character

Actor Chris Pratt helped to surprise families at a children's hospital in California on Wednesday (20Aug14) by visiting the medical facility in his Guardians Of The Galaxy costume.

The star teamed up with organizers at Marvel and Children's Miracle Network Hospital to host a special screening of the film at Children's Hospital Los Angeles.

During the screening, Pratt slipped out of the room to change into his costume.

He reappeared as Star-Lord and spent hours posing for pictures, signing autographs and handing out movie-themed toys to the young children.

Pratt has previously spoken about his desire to use the film's popularity to be a role model to his son and other kids.

He said, "I stole the jacket and some of the wardrobe so that, if this movie comes out and does what everyone hopes it can, I can follow the example of someone and go visit kids.

"If it was a big enough movie, to where it would mean something to a kid who's sick in the hospital - for Peter Quill or Star-Lord to come visit them - I'll do that. I think that's awesome, man. That would give me real meaning for this movie, you know?...

"Right now, it means high profile, cool jobs coming up, big press tour, and all the excitement of it all. But none of that really means anything. The coolest things would be that my son can one day see this, and that maybe I can go affect some kids in a positive way; be a good role model for them."