Young Adelaide dad dies in hit-run on Christmas Day

A family has spent Christmas grieving after a 23-year-old man died after being struck by two cars in Adelaide's northern suburbs, as police hunt for the driver of one of the vehicles.

John Mumme, who 9News has been told was expecting triplets, suffered critical injuries after he was hit by a white Mitsubishi Lancer and Holden sedan on John Rice Avenue in Elizabeth Vale late last night.

He was taken to the Lyell McEwin Hospital before being transferred to the Royal Adelaide Hospital where he died.

Mr Mumme's sister told 9News the victim was as an "amazing brother" who was there whenever she needed him.

"He was a great dad to his kids, anything he would do for the kids, he would do it," she said.

"His girlfriend is due to have triplets and he just found out that they are three girls. He was excited."

Police towed one vehicle from the scene but are calling on the driver of a second car believed to have also struck the man to come forward.

That car is described as a dark Holden sedan with possible front-end damage.

"Give us all the information you have got to lead to who it is, who they are. Anything can help," the victim's sister said.

"Honestly, just come forward and let us know who it is."

Police are asking anyone who witnessed the crash who has not yet spoken to them to contact Crime Stoppers.

They are also urging any crash repairers who may receive information regarding the described car to come forward.

The young man's death brings the number of lives lost on Adelaide roads to 108, compared to 75 at the same time last year.