Twice a week, Dexter the dog springs down his front steps in Lakeview for a pack run with his best friends. Dexter is 15 years old, a bona fide senior dog, and weighs 50 pounds. When he sees his canine companions, Sadie and Zooey, he wiggles his whole body then jumps on them to say hello. The routine started in 2015, when Dexter went on a pack run coordinated by a business called Chicago Dog Runner. Dexter’s mom, Stephanie Klein, was managing a busy schedule when she signed him up. “I wanted him to have an outlet and a way to get his energy out and be out and about,” Stephanie said. “See the world.” Through that business, Dexter became friends with Sadie — an 11-year-old, 50-pound Mountain Cur mix — and Zooey, a 12-year-old, 50-pound cattle dog mix. They’ve been running with Dexter, a boxer mix, for years, rain or snow, with only vacation or occasional injuries keeping them apart. I know Dexter through Sadie, the dog I share with my partner, who took her to Chicago Dog Runner for similar reasons as Dexter. We take it for granted, but Dexter is a real part of our lives. He’s our best friend’s best friend. But now he is moving to Arizona with his mom, her fiance, and a 6-pound Pomeranian, Bella, who can’t keep up with the bigger dogs. They’re trading skyscrapers and streetscapes for cactus and palm trees. Greta Kauffman has been the dogs’ runner for years. Most people don’t know there are dog running businesses. When Greta tells people about her job, they often respond, “Oh, you walk dogs?” “I say no,” Greta recalled. “I legit run them.” Greta Kauffman runs with Dexter, Zooey and Sadie, Dec. 10, 2024. (Eileen T. Meslar/Chicago Tribune) They usually get between 2 and 3 miles, though they would do 4 or 5 miles back in the day. After each run, Greta sends out personalized emails called “Pupdates” to the families detailing the day’s activities. It includes information about their route, any shenanigans and whether they voided. Voided is a polite society term for bodily functions. Greta usually includes cute photos of the four-legged creatures and posts highlights on social media. Sadie and Dexter love wading in kiddie pools on the street. (Zooey does not.) During this year’s first snowfall, Greta posted a picture of Dexter and Sadie muscling through the white. “Head down and power through the blowing snow, Sadie!” she wrote, in Dexter’s voice. “We’ve got this.” In another picture, she captured Sadie and Dexter outside the Tin Lizzie bar, famous for offbeat fun. “Are you looking to register for the turtle races?” Sadie asked, according to the caption. “Speak for yourself, Sadie,” Dexter responded. Each of the dogs has their own personality, Greta said. Sadie is the independent dog who “wants to do what she wants to do.” Zooey is a “scavenger,” happy to bring up the rear. Dexter is just “along for the ride. He will do whatever.” Dexter does sometimes cause a little trouble, Greta said, when he “gets a little too fresh with either of the girls” but he’s “learned not to do that so much.” “They’ve put him in his place,” Greta said. The pupdates have made us laugh for years. While the girls might void once on a run, Dexter regularly poops about half a dozen times. I didn’t lead with the hound’s bowels when I interviewed Stephanie, but I did ask her why he goes as often as he does. “I’ve always wondered, what do these owners think of Dexter’s poops?” Stephanie told me. She said it’s just the way he is, not a sign of neglect. “You can mention it” in this story, she joked, as long as I clarify that they do walk the dog without Greta too. Greta Kauffman runs Sadie, from Kauffman’s left, Dexter and Zooey in West Town on Dec. 10, 2024. (Eileen T. Meslar/Chicago Tribune) For Stephanie, the pupdates offer more than humor. They’re a source of inspiration. “Sometimes I see their adventures and I think, I need to get out more and have more adventures with myself, my fiance, my friends. Seeing the city through their eyes — they’ve seen so many murals I haven’t seen in person. So I think there’s something to be said there,” Stephanie said. “I know sometimes she’s taken them to the lake and the city with the skyline in the background. I say, we need to take that walk.” I will miss hearing about the trio’s adventures, such as the time Dexter flipped Sadie with his head to catch a sniff of something she was standing over. I think the dogs will miss the pack. When Dexter doesn’t immediately see the girls, Greta said he will look disappointed, like he’s wondering, “Where are my friends?” I believe Dexter will make new ones. That’s part of life. Sadie and Zooey will carry on with Greta. Still, it is hard for the humans, especially Greta. “The longer that I’m around them, the stronger the bond that I develop, too, and it’s a tough pill to swallow when they move,” Greta said. While talking to Greta and Stephanie, I asked: “Do you think they love each other?” “Dexter loves the girls,” Stephanie said. “I don’t know if the girls love Dexter as much as he loves the girls. I know he’s always all over them, excited to say hi. They definitely have a strong bond.” Greta’s answer was simpler: “In their own kind of unique ways.” For the record, Sadie loves Dexter enough to tolerate him more than she does any other creature, even me. I asked Greta what she’s learned in 14 years as a dog runner. “They’re a constant reminder to stop and enjoy the present,” she said. “Don’t take things so seriously. Find humor.” Dexter may not run Chicago’s streets anymore, but Stephanie hopes to find someone who can take him out in Arizona. Maybe they’ll run together in the cool desert mornings. Stephanie is also pondering whether she can teach an old dog new tricks. She’s going to buy him a life jacket and let him swim in a pool. He loves the water, but she’s never let him loose. “I think he’s a water dog at heart and I want him to have that experience if he wants to.” Life is always a new adventure, even for a dog.