Jimmy Kimmel Tearfully Reveals Newborn Son Billy Underwent Open Heart Surgery

Jimmy Kimmel and his wife Molly McNearney welcomed their second child together, William John “Billy” Kimmel on Friday, April 21. But at three days old, Billy had to have open heart surgery at Children’s Hospital Los Angeles.

The late-night talk-show host tearfully revealed on Monday’s show that his newborn son had successfully undergone the life-threatening operation.

“We call him Billy. Six pushes, he was out. He appeared a normal healthy baby,” Kimmel, 49, began his opening monologue while fighting back tears.

Want all the latest pregnancy and birth announcements, plus celebrity mom blogs? Click here to get those and more in the PEOPLE Babies newsletter.

The new parents were moved to the recovery room, where the couple’s older child, 2½-year-old Jane, was there to meet her baby brother, who was named after Kimmel’s longtime TV partner Guillermo. (Guillermo is the Spanish form of the name William.)

But three hours later, a nurse noticed something was wrong with Billy.

“My wife was in bed relaxing. A very attentive nurse at Cedars-Sinai heard a murmur in his heart and noticed he was a bit purple, which is not common,” Kimmel explained.

“[Nurses] determined he wasn’t getting enough oxygen in his blood, either in his heart or lungs … It’s a terrifying thing, you know, my wife is back in the recovery room, she has no idea what’s going on.”

Billy’s heart surgeon explained to Kimmel and McNearney that their son was born with a congenital heart disease, called tetralogy of Fallot with pulmonary atresia. “Basically, the pulmonary valve was completely blocked and he has a hole in the wall between the left and right sides of his heart,” Kimmel said.

On Monday morning, Billy successfully underwent open-heart surgery. “He’ll have to have another open-heart surgery in three to six months,” Kimmel shared, adding that Billy will need a third “hopefully non-invasive procedure” when he’s in his early teens.

“Poor kid. Not only did he get a bad heart, he got my face,” Kimmel lightheartedly joked.

Six days after he was born, Billy was able to leave the L.A. hospital and go home.

Kimmel was sure to thank his friends and family and, shockingly, even Matt Damon.

“Every one of my friends was there 100 percent. We had atheists praying for us, okay? We had people who do not believe in God praying to him. And I hate to even say, but even that son of a bitch Matt Damon sent flowers.”

But he saved his kindest words for Billy’s amazing mother.

“Most of all, I want to thank my wife Molly. First of all, for allowing me to have sex with her in the first place,” he joked. “Also for being so strong and level-headed and positive and loving during the worst nightmare a new mother could experience.”

“I couldn’t ask for a better partner. I’m so happy we had this baby together. I’m definitely getting a vasectomy after this.”

The couple announced they were expecting their second child together in early December 2016.

Kimmel, who’s also dad to older kids Kevin, 23, and Katie, 25, told PEOPLE last year that fatherhood is “really great.”

And despite having initial jitters about being the father of a little kid again, he said, “It does add a little bit of joy to each day. Maybe more than a little bit.”

RELATED VIDEO: Jimmy Kimmel Explains the Challenges of Potty Training

Kimmel is now on paternity leave for the rest of this week, and his famous friends will guest host the ABC show in his absence. Here’s the lineup:

Tuesday: Host Will Arnett, with guests Maya Rudolph and Ben McKenzie and musical guest Incubus

Wednesday: Host Anthony Anderson, with guest George Lopez and musical guest Future

Thursday: Host Kristen Bell, with guests Charlie Hunnam and Adam Scott and musical guest Alison Krauss

Friday: Host David Spade, with guest Guy Ritchie and musical guest alt-J