Jason Aldean and his wife, Brittany Aldean, performed a heartfelt duet of Luke Bryan's song "Drink a Beer" in honor of slain conservative activist Charlie Kirk.On Tuesday, the 48-year-old country star and the 37-year-old former "American Idol" contestant shared a joint Instagram post that featured a black-and-white video in which they sang Bryan's 2013 ballad about the unexpected loss of a loved one. Jason was seen seated on a counter as he played a guitar while Brittany stood beside him."For Charlie," they wrote in the caption with a red heart emoji.CHARLIE KIRK REMEMBERED BY COUNTRY MUSIC STARS AS ONE OF THE GREATEST YOUNG PATRIOTSThe video began with an image of the couple that was taken during Kirk's memorial service Sunday. Jason and Brittany were seen from behind as they stood with their arms around each other and faced the stage at State Farm Stadium in Glendale, Arizona.The pair were among the nearly 100,000 attendees who gathered to mourn the loss of the Turning Point USA founder after he was shot and killed while speaking outside of Utah Valley University on Sept. 10.On Monday, Brittany took to Instagram to detail the service for her followers. She admitted that the day "was overwhelming," but said that she was inspired by how Kirk "impacted people.""Yesterday we went to Charlie's funeral service in Arizona, and it was vastly different than what I anticipated in the sense that it was just so faith-based," Brittany began. "I knew it was going to be, but everyone was worshiping everybody. There was just something different in the room."President Donald Trump, Erika Kirk, Vice President J.D. Vance, United States Secretary of Health and Human Services Robert F. Kennedy Jr. and Secretary of State Marco were just a few of the speakers to eulogize Kirk during the service.SAVANNAH CHRISLEY SAYS OUR LIVES ARE ON THE LINE FOLLOWING CHARLIE KIRK'S DEATH, VOWS TO FIGHT ON"This man's legacy that he has left, the impact that he's had on so many people Like, I knew he had impacted a ton of people, but this feels different," Brittany said. "His death does feel like everyone said in the services a revival. It's putting more people in touch with their faith, and just making such a difference in so many different lives, and it was very apparent yesterday."She noted, "It was overwhelming. I expected to go in there and cry the whole time. I brought this big thing of tissues, and instead, it was weirdly positive and extremely sad, but it was awesome to hear stories about him personally and how he's impacted people, and how he's going to be so missed, but that his legacy was so large.""He had a different purpose in life, and it was just so good to hear people say that. There was just a different plan that was greater for him that God knew," Brittany added. "It left me feeling more positive after the service, and he's obviously so missed. Something's different about this."Brittany left her followers with the note, "They keep saying live like Charlie, so I'm going to really try to do that daily."On Sept. 11, Jason paid tribute to Kirk during a concert in Detroit, Michigan.At one point during the show, he took a moment to speak about Kirk and the impact he had on his life and career."An amazing person by the name of Charlie Kirk was murdered yesterday in Utah," he told fans, as seen in video captured by an audience member.Cheers erupted at the mention of Kirk's name, and Jason continued to explain that he knew Kirk personally and had the opportunity to meet with him multiple times over the past few years."One of the best people ever," he said of the late Turning Point USA founder. "This is not the guy you go after, is what I'm trying to say."LIKE WHAT YOURE READING? CLICK HERE FOR MORE ENTERTAINMENT NEWSHe continued, "And it's a weird country that we live in when you start taking people out because you disagree with their opinions. That's not what we're about here."Jason went on to talk about his 2023 single, "Try That in a Small Town." At the time of its release, the song and its accompanying music video were met with backlash and the video was pulled from the Country Music Television (CMT) network's rotation."I remember when we put this song out, people like Charlie Kirk were some of the first people to come up and go, Thats what it's about. This country coming together, calling out the bulls--- when we see it, trying to get everything back on track,'" he said.CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER"This guy wanted nothing more than what was best for all of us, and for our kids moving forward," he continued."Charlie is a guy that's going to be very, very much missed, and this is something that his legacy is going to live on forever with Turning Point [USA] and what he's done with only 31 years on this planet, it's amazing."He went on to perform "Try That in a Small Town" in honor of Kirk.Authorities identified Kirk's murder suspect as Tyler Robinson, 22. He was arrested on suspicion of aggravated murder, felony discharge of a firearm causing serious bodily harm and obstruction of justice charges, according to a court affidavit. A judge ordered that he be held without bail.Robinson was later charged with aggravated murder, two counts of obstruction of justice for hiding the rifle and discarding his clothing, two counts of witness tampering for instructing a roommate to delete texts and stay silent and one count of committing a violent offense in front of children.Fox News Digital's Tracy Wright and Emily Trainham contributed to this report.