ABC announced on Monday that Jimmy Kimmel's seven-month-old son Billy "had a scheduled and successful heart surgery this morning".
Billy was born last April with heart defects that required surgery immediately after his birth to fix a blocked pulmonary valve, allowing blood to reach his lungs to be reoxygenated.
The defects meant that Billy wasn't getting enough oxygen in his lungs when he was born because he had a blocked pulmonary valve and a hole in his heart. Monday's procedure was originally set for late October, but it was delayed "due to the common cold", according to People.
He explained a nurse was checking him over and noticed a murmur in his heart and he looked a little purple.
Kimmel and his wife, Molly McNearney, are also parents of daughter Jane, 3.
Chris Pratt will be the first of several guest hosts filling in for Kimmel. Tracee Ellis Ross, Neil Patrick Harris and Melissa McCarthy will follow.
Pratt hosts tonight's show, with guest Margot Robbie (I, Tonya) and a performance by country star Chris Stapleton.
Retired 'Hero' Army Dogs Saved From Being Put Down
Hundreds of thousands of people joined the campaign to stop the two dogs, along with police dog Driver, from being put down. If, at the end of de-training, dogs are considered too old, dangerous, below standard, ill or unfit, they will be put down.