Jimmy Kimmel's "little fighter" of a son turned 1 on Saturday following a year of heart surgeries, and the late-night comedian marked the occasion with a sweet Instagram photo.
Kimmel shared a photo of son Billy to social media, featuring the smiley tot decked out in a birthday hat and bowtie.
Billy was born in April 2017 with a congenital heart condition that forced him under the knife twice in his first year; once three days after he was born, and once again in December.