By JEFFREY A. JOHNSON and MEGAN TRIMBLE, PennLive.com

The days leading up to Thanksgiving have been a gut-wrenching struggle for Theresa Allocca.

It has been nearly 11 months since her son, Timothy Davison, was shot and killed along Interstate 81 following an apparent road rage incident.

This will be the first Thanksgiving Allocca and her family experience without her son, whose killer remains at large.

"We don't know if we'll leave an empty place setting [at the table]," Allocca said in a recent phone interview from her home in Maine. "We've always kind of shared the holidays with him.

"Many people in the family wish the holidays would just pass and we could forget about this whole chapter," Allocca added.

State police continue to investigate Davison's killing, which occurred in the early mornings hours of Jan. 4. Davison was driving north after visiting friends and family in Florida when a pickup truck forced his vehicle into the median of I-81 in Franklin County, state police said.

Authorities believe someone inside the truck shot Davison, 28, before driving off in the opposite direction. Troopers have released a detailed description of the truck, which still elicits tips from the public.

But state police spokesman Trooper Rob Hicks said state police have no new information to release about the case, which garnered national headlines when it happened.

Allocca said she has kept in weekly contact with state police and believes her son's killer will eventually be apprehended.

"I have no doubt. At some point, it might end up being a cold case. Who knows?" Allocca said. "But I think this person will eventually get caught doing something else or turn themselves in. I find it hard to believe that someone would do this and get away with it forever."

Davison, nicknamed Asti, was from Poland, Maine. His mother described him as a "gentle giant." He was the kind of person you could call at 3 in the morning if you had a flat tire, his mother said.

He also enjoyed the outdoors and took a particular interest in snowboarding and "mudding," a form of off-roading.

He worked as a foreman for his father's pipe fitting and industrial construction company based in Raymond, Maine. His father, also named Timothy Davison, said his son was known for being skilled with his hands and a great mechanic.

The elder Davison, who is divorced from Asti's mother, said he thinks about his son every day and his absence spreads to others in the family, including his younger siblings.

"To be honest, the situation is bad, and it's not getting any better," he said. "Asti is missed every single day tremendously by so many people."

Davison's father also said the investigation of his son's killing has frustrated him, to the point where he no longer speaks with police.

He said he has also become frustrated and angered the case has been used as fuel in pro-gun and anti-gun debates. It has reached the point where the elder Davison said he has stopped reading media coverage of his son's killing.

He is not sure he wants to see the face of the person who killed his son, friend and employee who was "an intimate part of [his] life for 28 years."

"It is literally crazy to think a person believes they can [kill someone] and to have done it. It's beyond my thought process," Davison said.

Allocca said she continues to receive help from several people in various states who have offered to hang flyers detailing specifics on her son's killing along the I-81 corridor.

There are also plans to erect a billboard with information on the case along I-81 close to where the shooting occurred, Allocca added.

PA Crime Stoppers and Davison's family are offering separate rewards for information that leads to an arrest and prosecution in the case. The Crime Stoppers reward is $10,000 and the family has raised roughly $12,000, Allocca said.

State police are asking anyone with information in the case to to contact PA Crime Stoppers at 800-4PA-TIPS (800-472-8477).

To learn more about Timothy Davidson and how you can help, visit the family's website at www.justiceforasti.com or its Facebook page.