RICHMOND, Va. -- Do you believe in the power of prayer? Karen Kirby does.
Her son Grayson was nearly killed in 2014 when he was thrown from a truck that flipped in a crash.
With her son in the hospital, Kirby set-up a Facebook page and asked for prayers.
Thousands of prayers and positive messages came in from around the world.
Ten weeks after the crash, Grayson was released from the hospital.
Karen Kirby said doctors at the University of Virginia hospital could not explain her son's quick recovery.
"I guess that's not a question for us to answer," she said. "God has a purpose and a reason for everything he does and maybe one day we will find out."
But can prayer really help heal someone?
"I think it’s not only possible, that prayer could help a medical outcome, but it’s very, very likely," Dr. Harold Koenig, with Duke University, said.
But Dr. Richard Sloane disagreed.
"For every person who’s recovering like that, there may be hundreds of thousands of people who also were prayed for who aren’t recovering," the Columbia University Medical Center doctor said.
Others, like neuropsychologist Brick Johnston, said what was most important was spiritual beliefs.
He said believing in God, or simply having a group of people in their corner, can help inspire the sick back to health.