Jimmy Kimmel Celebrates Son Billy's 5th Birthday, Says He's 'Grateful' for Doctors Who Saved Him

Jimmy Kimmel/Instagram; Getty

Jimmy Kimmel is feeling grateful as he celebrates his son William "Billy" John's 5th birthday.

On Thursday, the talk show host, 54, paid tribute to his son with a sweet post on Instagram, in which he expressed his appreciation for the doctors and nurses that helped to save Billy, who was born with a congenital heart condition.

"Happy 5th birthday to our little nut. We are eternally grateful to the brilliant doctors and nurses at @ChildrensLA & @CedarsSinai for saving Billy's life and to those of you whose donations, prayers and positive thoughts meant everything," Kimmel writes. "Please support families who need medical care. Link in bio. 💙"

In the adorable photo, Billy smiles as he sits in front of a small cake decorated with three birthday candles.

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Kimmel and wife Molly McNearney overcame a hard first year with their baby son, as he had to undergo three heart surgeries (one when he was just three days old) after he was born with the congenital heart condition, tetralogy of Fallot with pulmonary atresia.

The talk show host — who also shares daughter Jane, 7, with McNearney and has two older children, Kevin and Katie, from a previous relationship — first opened up about his son's situation in May 2017, with a tearful monologue on his show. And in April 2018, Kimmel shared details with Oprah Winfrey about the feelings of detachment he and his wife felt, out of fear.

"There were secrets we kept from each other that we revealed only after the second surgery. The biggest one was that, I think subconsciously, we didn't want to get too close to the baby because we didn't know what was going to happen," Kimmel said in an interview for O, The Oprah Magazine's April 2018 issue.

In October 2020, Kimmel shared never-before-seen glimpses of his youngest child's health battle in order to encourage fans to "vote with your heart."

During an episode of Jimmy Kimmel Live!, he introduced a video segment that tracked the hospital visits and surgeries he and McNearney attended for their then-newborn son, Billy.

Through the video, McNearney presents photos and clips of Billy just after birth, his stint in the NICU, and during his many hospital visits. The video points out Billy's three heart surgeries and says he has had over 60 doctor appointments in his three years of life.