“Thanks to those loving strangers who took time to pray for and send positive energy to our baby, 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.”

“Walking around this hospital, 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.”

Kimmel expressed his gratitude for his son’s health, saying: “There are so many parents and children who aren’t fortunate enough to go home after five days.”

The doctors did an echocardiogram, which is a sonogram of the heart, and found that Billy was born with a rare congenital heart defect called Tetralogy of Fallot (TOF) with pulmonary atresia – in which there was a hole in the wall separating the two sides of his heart.