Jimmy Kimmel's son has third open-heart surgery

Jimmy Kimmel's son has undergone his third open-heart surgery.

The late-night host thanked healthcare workers at Children's Hospital Los Angeles for their care and commitment to his son Billy's successful surgery.

"We went into this experience with a lot of optimism," Jimmy wrote on Instagram, alongside a photo of Billy, seven, in hospital, "and nearly as much fear and came out with a new valve inside a happy, healthy kid."

The surgery marked Billy's third open-heart operation, with the first taking place only hours after he was born.

"Walking around this hospital," Jimmy, 56, continued, "meeting parents at their most vulnerable, children in pain and the miracle workers who do everything in their considerable power to save them is a humbling experience."

He went on to express gratitude to family and friends, as well as fans for their support.

"Thanks to those loving strangers who took time to pray for and send positive energy to our baby," Jimmy added.

"Thanks to our family and friends for rallying around us to an almost-ridiculous extent, thank you to my wife Molly for being stronger than is reasonable for any Mom to be and Billy, you are the toughest (and funniest) 7 year-old we know."