When Jonathan O'Shaughnessy turned 18, his father, Brian, bought him a tattoo of the Celtic cross. "Johnny," as dad called him, couldn't wait until spring when he could wear a tank top and show off the forearm tattoo and a slogan in Gaelic: "Loyalty to the end."

The tattoo symbolized Jonathan's devotion to his heritage and family, a trait that epitomized the young man right up until the moment he was gunned down in a drive-by shooting after accompanying family members to a celebration in Richfield on July 3. Jonathan was shot four times by someone inside a van as he walked away from the event.

It had started out as a night of fun, with Jonathan using social media to chronicle the group laughing and dancing at the community party. Brian said his girlfriend's daughter got a Snapchat message from Jonathan later that night.

"She snapped him back at 11:10, but he never answered," said Brian. "He was dead."

Jonathan, 24, was given CPR by a family member and responders, but he died at the scene.

"There were a couple of cops there with tears in their eyes, and some were angry," said Brian, whose dad was a police officer. "It's their town."

The shooting was only a block and a half from the party, so there were a lot of people around, including two bicycle riders who stopped at the scene, then left. The cyclists never called 911. Richfield police, who have discovered no connection between the victim and the shooters, have called for the bikers, or anyone with evidence, to come forward. Witnesses saw a gray minivan leaving the scene. The family has offered a $10,000 reward on top of a $4,500 reward from Crime Stoppers.

Brian, a burly, bearded guy, now lives in Bay City, Wis., but has spent his life as a bartender, manager and bouncer, often in some of the tougher establishments in town. At a Minneapolis coffee shop Tuesday, he was just a sad man who had lost a son, a guy forevermore on the lookout for a gray minivan.

Wearing a Tommy Bahama T-shirt, a bracelet Jonathan bought in Ireland and a hat with the name of his son's recent employer on it, Brian O'Shaughnessy looked weary from grief. "I'm Irish, so there's anger, too," he said.

"Jonathan was just one of the most decent young men you'd want to meet. He was a good guy, the complete opposite of the person who shot him."

Brian said he and Jonathan's mom never married, and they separated shortly after their son was born. But they lived just a mile apart, and Jonathan split time between them, often biking to his dad's house, where he also had a room.

"We're united on this," Brian said. "We're as one."

"For his mom, it was always 'Jonathan,' " Brian said. "The kids at school called him Johnny O'. To me, he was Johnny, with dirt in his mouth and mud on his hands. He was a stud. He ran track and lettered as a freshman" at his school, Holy Angels. He lived across the street from school, and had many longtime friends from the neighborhood.

"He and his mom were very close," Brian said. "They took trips every year and had breakfast every weekend. She's very strong."

The two, Jonathan and mom, would often go to Perkins, in Bloomington, and would flip a coin to see who would pick up the tab of a veteran or senior citizen sitting nearby.

On Facebook, Jonathan's mom wrote:

"My world has come crashing down around me … you are such a fabulous person and I just can't imagine my life without you … My heart is broken and I still am waiting for you to come walking through the door. I cannot believe such a senseless act could have happened to our family. No words can explain our pain. We know the police will catch and prosecute the people that shot you but that does not bring you back. My son it is a honor to have been your mom and like we always said 'never goodbye — always cya soon.' "

Jonathan had an adventurous spirit, traveling around the world in his early 20s. In Ireland, he kissed the Blarney stone, which is said to give the gift of gab.

"But he already had that," said his dad.

When Brian's longtime girlfriend, Gail, was diagnosed with breast cancer a few years ago, Jonathan was there to help. "All through high school he lived with that," his dad said. "He was standing next to me when she died in our living room."

Police aren't saying much, but Brian thinks the shooting may have been a gang initiation. He doesn't believe the shooters and his son had an altercation that led to retaliation. "If he'd bump someone and knocked their beer out of their hand, he would have bought him a new one," Brian said. "There was just no beef in him."

Brian has a hard time believing no one leaving the event saw anything that could help. "A dent in the fender, an arm out the window, anything," he said.

Jonathan was about to start a new job with a heavy equipment company, and he'd just bought a new car, a Mitsubishi Lancer. He looked forward to driving it to visit his dad in Bay City along the scenic, winding Great River Road in Wisconsin.

Brian O'Shaughnessy put his hands up at 10 and 2, as if to take his son's car in his hands.

"You know, just get out on the highway and open it up a little bit," he said. "Lean it into the curve."

jtevlin@startribune.com • 612-673-1702

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