The father of four shared the news of Billy's open heart surgery with viewers on Jimmy Kimmel Live! in May, telling ET that having to share the news with the public "wasn't great."
"It's one of those things that happens and it's terrible and then you realize, 'Oh, I have to say something about that. There's parents who have to deal with a lot worse than we're dealing with, so we're keeping it in perspective."
Kimmel's wife, Molly McNearney, shared similar sentiments while chatting with ET's Lauren Zima.
"It's been a rough start with Billy, but he’s doing great. He has another surgery coming up and then we’re out of the woods for a while. And our 3-year-old [daughter, Jane] loves him. Like, maybe a little too hard," she said. "But it’s been really good."
"He’ll have another open heart surgery at the end of October and then he’ll have another one much later when he’s eight or 10 years old. But he’s doing really well. We’re at Children’s Hospital again and we have a great team there and we feel really optimistic about it," she added. "It really, actually makes me complain a lot less about stupid things. You know, when we had our 3-year-old, very healthy, we took that completely for granted. I have so much respect for people who are in that hospital with sick children and going through that."
In addition to the doctors taking care of their son, McNearney said she and Kimmel leaned a lot on each other for support.
"Thank God for [Kimmel], he was amazing. Each day we were the other one’s rock," she shared. "He kept things actually funny and uplifting and we cried together a lot, but thank God we had each other through all that."