Dad of Deceased Chiefs Fan Doesn’t 'Really Care' What Investigation Turns Up: 'Not Going to Change Anything'

“I’ve already said my goodbyes to David," dad Jon Harrington tells PEOPLE

• David Harrington's father is speaking out about the death of his son

• “I’ve already said my goodbyes to David and it’s not going to change anything," Jon Harrington tells PEOPLE amid the ongoing death investigation

• One source of comfort for the father has been knowing David had many friends who attended the 37-year-old's celebration of life service in January

The father of David Harrington, one of the three Kansas City Chiefs fans who were found dead in their friend’s backyard on Jan. 9, says that no matter what police find amid their ongoing death investigation, nothing will ever be able to change the fact that his son is gone.

“I don’t really care what they find out now. It doesn’t matter to me,” Jon Harrington, 57, tells PEOPLE. “I’ve already said my goodbyes to David and it’s not going to change anything.”

That's how Harrington recalls thinking when news of their mysterious deaths first gripped the nation. Over a month later, he says, "I still feel that way."

“I suppose we’re having to go on with our lives," he adds. "That’s what’s going to happen one way or the other.”

Related: Father of Chiefs Fan Found Dead in Yard Speaks Out: 'There Will Be a Wrongful Death Lawsuit'

The Dearborn, Missouri, resident tells PEOPLE that he received confirmation around Jan. 11 that his 37-year-old son, along with Ricky Johnson, 38, and Clayton McGeeney, 36, had died, after their bodies were found outside their friend Jordan Willis’ rental in Kansas City two days earlier.

As the father continues to process the loss of David, he says he took comfort in knowing that many of his friends turned out for a celebration of Harrington’s life on Jan. 21, where they came together at a golf course clubhouse to honor the man, while doing what he loved, watching the Kansas City Chiefs play.

“I couldn’t have imagined a better way to send him off than that," he says.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.

"There’s parts of that day that I will remember ‘til the day I die,” Harrington says.

He adds that an "awful lot of people" were in attendance, which "just told me how much they were missing him."

Harrington, who says he hasn’t heard any updates from police in over a month, shares Kansas City Police previously read him the results of a toxicology report saying cocaine and fentanyl were found in his son’s body. (The autopsy and official toxicology reports have not been made public.)

“I believe he intended to get drunk," he says. "But the [drugs] – I’m not buying that. I’m not arguing that that was what they found in his system, but how it got into the system, we still don’t know.”

As they wait for more information, the Harringtons have launched a T-shirt campaign, selling shirts to help keep the men’s names in people’s minds and their memories alive. A GoFundMe was also created to help David's father.

Related: Father of Chiefs Fan Found Dead in Yard Speaks Out: 'There Will Be a Wrongful Death Lawsuit'

A spokesperson with the Platte County Prosecutor's Office told PEOPLE Thursday that there was "nothing new to report" and the case is under investigation by the Kansas City Police Department.

Police confirmed with PEOPLE on Friday that detectives are "continuing to investigate this case, however, there have not been any significant updates to provide at this time" and that the case remains a death investigation and "NOT a homicide investigation."

John Picerno, who represents Willis, previously said that his client “is unaware of how his friends died" and was “anxiously awaiting the results of the autopsy and toxicology report.”

For more People news, make sure to sign up for our newsletter!

Read the original article on People.