Jimmy Kimmel's son's heart surgery has been postponed.

The 49-year-old presenter's six-month-old son Billy was due to undergo an invasive operation, after he was born with a congenital heart defect and needed immediate surgery, but the follow-up procedure was cancelled because the family have been hit with colds.

The 'Jimmy Kimmel Live!' host's publicist confirmed the treatment has been pushed back as a precaution in a statement released on Monday (30.10.17).

Jimmy - who has Katie, 26, and Kevin, 24, with former wife Gina, and three-year-old Jane, as well as Billy, with spouse Molly McNearney - is taking a week's break from his talk show to be with his family, even though the surgery is no longer taking place.

During Jimmy's absence Shaquille O'Neal - who filled in on Monday - 'Magic Mike' actor Channing Tatum, 'Mother!' actress Jennifer Lawrence, and Foo Fighters frontman Dave Grohl will front his popular ABC show.

Billy will still have to undergo more operations in the coming months, and Jimmy has admitted he's nervous for the procedures and wants to get them ''over with''.

Speaking previously, he said: ''He has to have two more open heart surgeries. We would like to get them over with and not have to think about it all the time, but it could definitely be worse.''

But despite Billy's condition, he is still a ''healthy and happy'' child.

Speaking previously about how his tot is coping, Jimmy said: ''Young Billy is six months old today. 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. (sic)''