Ciara and Kelly Rowland sing Christmas carols at children's hospital

Ciara and Kelly Rowland spread some festive cheer as they sang Christmas carols at a children's hospital in Seattle.

The Grammy award-winning R&B stars surprised patients and their families at the Seattle Children's Hospital on Friday (15Dec17), and performed while accompanied by guitarist Barry Black.

Ciara and Kelly had also teamed up with online store Amazon, and presented the kids with a six-foot tall gift box filled with Amazon products, and took photos with the happy patients.

Suzanne Weir, mother to five-year-old Pascuala Mejia-Canastuj who recently underwent a liver transplant, said the visit enabled her to take her mind off her daughter's health problems.

"They brought a smile to these kids' faces," she posted in the comments on the hospital's blog. "It helped get our minds off things and made us feel better. I felt like a weight had been taken off my shoulders. We could just relax and have fun."

Kelly posted a shot of her and Ciara performing to a little girl in a hospital bed on Instagram on Friday (15Dec17) and couldn't hide her delight at bringing some Christmas cheer to the patients.

"Thank you so much to @ciara & @seattlechildrens For having me!" she captioned the snap. "The smiles I saw yesterday made my heart smile! I had so much fun!!! Can't wait to do it again! XO."

Ciara shared a series of snaps on Instagram, including a video of her singing Jingle Bells with a girl called Erin. "Today Was A Dream Come True! Singing Christmas Carols with my girl @KellyRowland to the RockStar Patients of @SeattleChildrens. @WhyNotYouFDN #StrongAgainstCancer," she wrote alongside snaps including one of her rocking out with a young patient.

Ciara and husband Russell Wilson, quarterback for the Seattle Seahawks, visited the hospital on Tuesday (12Dec17). "Keep being strong and inspiring us all!" the Goodies hitmaker captioned pictures of the couple visiting children.