"Young Billy is six months old today," he wrote on Instagram Saturday. "He is healthy and happy and we are all very grateful for your prayers, good wishes, thoughts and support of @ChildrensLA and children's hospitals in your area."
Kimmel's young son first came into the spotlight barely a week after he was born. The Jimmy Kimmel Live host returned to the show to explain that Billy had to undergo open heart surgery.
During that monologue, which now has more than 11 million views, Kimmel reflected on how difficult it is to be the parent of a baby with a health condition.
"If your baby is going to die and it doesn't have to, it shouldn't matter how much money you make. I think that's something that whether you're a Republican or a Democrat or something else, we all agree on that, right?" he said. "No parent should ever have to decide if they can afford to save their child's life."
Kimmel said at the time that his son would need another open-heart surgery in three to six months. He'll also need a procedure to replace the valve, probably in his early teens.
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