Four-year-old asks Santa to pray for sick baby he doesn't know

When 4-year-old Prestyn Barnette visited Santa at the mall, he asked for a toy train, but he didn't stop there. He also wanted Santa pray with him on behalf of a sick baby across the country.

"Baby Knox" is in a hospital in Las Vegas, but Prestyn's family in South Carolina heard about his plight though of social media. Knox Joseph was found unresponsive on Nov. 30. His family wrote on their GoFundMe page that doctors advised them to take the baby off life support, but the family decided to keep fighting.

Prestyn's aunt, Rebekah Lauren Sharpe, explained to ABC that their family had been praying for the baby, so Prestyn felt a connection even though they're strangers.

"We found his page on Facebook and started following from there," she told ABC via email. "Prestyn knows about Knox through us, and from watching us pray for him throughout the day. In his nightly prayers he began to pray for Knox."

When Prestyn went to visit Santa at the Dutch Square Mall in Columbia, S.C., he had those nightly prayers in mind. His aunt recounted what happened:

"We just went for the routine Santa visit and when he sat down on Santa's lap he asked for a Lionel train and to pray for baby Knox. And Santa said alright [sic] got down on his knee and started praying out loud."

Baby Knox's family was touched by the sweet gesture and shared a photo of the moment on their Facebook page, "Team Knox Joseph," saying, "Even Santa Claus is praying for Baby Knox!"

The last update from Knox's family was that he was able to breathe at one point Monday night.