See Taylor Swift Sing to Young Boy With Cancer

— -- Taylor Swift made a visit to Boston Children's Hospital over the weekend and made one of her biggest fans very happy.

Jordan Lee Nickerson, 6, was diagnosed with Williams Syndrome, a "rare genetic disorder" when he was 9 months old, his Facebook page says.

"He has both physical and developmental disabilities. He also had a severe heart condition. At just 18 months old, he underwent open heart surgery to repair part of his aorta," the page continues. "On July 24, 2014, Jordan was diagnosed with Leukemia. He is currently in Childrens Hospital Boston and faces a long struggle."

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Jordan's favorite singer is Swift, so his little face lit up when she came to visit. The two played air hockey, sang and enjoyed lots of hugs. She even gave the little guy a big smooch on the cheek.

One video shows Swift, 24, singing "We Are Never Ever Getting Back Together" while Jordan sings along in his little Spider-Man t-shirt. Jordan also dances and just looks so happy to see his idol. It's a nice moment in an otherwise tough road for the young boy.

In another clip, Jordan schools Swift during a game of air hockey. He's competitive, but very polite!

The hashtag for this sweet little guy on his page is #Jordanstrong.