As the parents of Ethann McAuley put their son to rest, they pleaded for the driver who fled the scene of the York Region collision that claimed his life, to come forward.

The 20-year-old Orillia native was struck by a northbound vehicle while walking on Highway 404, near Major Mackenzie Drive in Markham on April 23, at around 10:30 p.m.

“I just think what this person did was horrendous and I don’t want any other family to ever have to go through all of this, burying their son,” Janette Harmer, McAuley’s mother, said as she held back tears at his funeral.

“Turn yourself in; it’s the right thing to do. Whether it was unavoidable… it doesn’t matter. You don’t leave another human being on the side of the road.”

It’s still unclear why he was walking on the highway, but his family believes the first-year Seneca College student may have been out clearing his head.

“The highway was right there,” Harmer says. “We think maybe he went for a walk and got turned around and didn’t know how to get back.”

The OPP says they have found “nothing suspicious about his activities at this point.”

During a news conference on Thursday, the investigators said it’s possible the driver couldn’t avoid McAuley. However, the OPP believe the driver would have known the collision happened.

“If that person believes that maybe it was an animal or a piece of debris and they didn’t realize what they had hit until they got home -- We just want to talk to that person,” OPP Sgt. Kerry Schmidt said.

Part of the suspect’s vehicle, including the front passenger headlight and a side mirror, was found at the scene by police. The vehicle has been described as a black 2011 or 2012 Hyundai Sonata.

Investigators believe the vehicle may have been repaired since the collision.

“If you know anyone with a vehicle like this, ask them to see it or where it is. Prove to yourself that they are not involved,” Schmidt said. “We have no idea who this person is.”

Anyone with information is asked to contact the OPP or anonymously, Crime Stoppers.

With files from CTV Toronto.