Knocking on a young patient's door, John McInerney peeks his head inside with a question that prompts a big grin.

"Hey, want to make a Lego robot?"

It's become a familiar scene at University of Michigan C.S. Mott Children's Hospital, where McInerney — or "Lego guy," as the kids call him — has become a new regular.

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Recognized by his rolling cart topped with a giant, bright-yellow Lego man head, the 24-year-old spends his days lifting young spirits with one of the most timeless toys.

Right from their hospital beds, Mott patients can choose from more than a dozen kits in the cart to assemble colorful Lego robots.

There's a frog whose motion sensor-activated tongue flicks out to catch a fly and a dump truck that empties its bed of Lego items into messy piles. Other options include a race car, submarine, airplane and dolphins.

With McInerney nearby to offer assistance, patients follow iPad instructions to build and program their Lego creations. The kits are designed for children as young as kindergarten so the experience can be "purely fun and stress-free," he says.

"For me, the best part is watching something I made come to life through the kids and see it bring smiles to their faces," says McInerney, who graduated from U-M's Penny W. Stamps School of Art & Design in 2016.

"These kids go through a lot, and I can't imagine spending that much time in a hospital room at that age."

What started as a few volunteer hours a week has evolved into daily visits by McInerney's new on-the-go robotics LLC, Buildup Mobile.

The bedside activity not only brightens young patients' days but also encourages STEAM (science, technology, engineering, the arts and math) learning while creating a natural social environment for patients to work on fine motor skills.

Mott has hired McInerney as a vendor, but the program relies on donor support.

An idea takes shape

Buildup Mobile isn't anything McInerney ever imagined using his design skills for.

But he says he realized how much he enjoyed working with kids at his former job at the Robot Garage in Birmingham, Michigan, which offers robotics classes and experiences to community youth.

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McInerney and his brother, Tom — both of whom were familiar with Mott because of friends who received care there — came up with the idea to offer a similar experience to patients.

With a PowerPoint presentation and single robot in hand for demonstration, McInerney explained his idea to J.J. Bouchard, Mott's patient technology coordinator.

Bouchard's response: "I love it."

From day one, Bouchard says, "Lego guy" was a hit. He receives multiple daily requests from families asking for a visit.

"John has a gift for connecting with patients and families. The kids just light up when they see him walk into their room with a cart full of Lego toys," Bouchard says. "His patience, imagination and passion for creative learning is contagious."

Building connections and comfort

McInerney, who estimates going through about 2,000 Lego pieces a day during Mott visits, designs most of his robots from a workbench at his parents' home in Birmingham.

But his creations are often inspired by the kids themselves.

Thirteen-year-old Xavier "Ziggy" Escamilla, for example, once helped McInerney add a penguin to the mix. As the two played with a robot, they decided one of the pieces could be a beak. They then added eyes and programmed it to waddle.

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"Some of the kids who I visit regularly have created all of my robots, so we have to come up with new ideas," McInerney says with a laugh. "We sometimes make new ones together. It's fun to involve the kids in the process and see how they can influence the designs."

Ziggy's mom, Prescilla, says her son has had several long hospital stays during treatment for a rare form of leukemia — which makes McInerney's visits a special reprieve.

"No matter how sick he feels, Ziggy loves to build with John," she says. "It distracts him from reality and puts a smile on his face.

Growth potential

The program also benefits children by encouraging early engineering and robotics learning and activating different parts of their brain — a particularly helpful benefit for children who spend long days in a hospital room.

"Building lets them practice those gross motor skills that you can lose from the side effects of chemotherapy and radiation," Prescilla Escamilla says. "It also allows them to use their imagination and make something fun while they're here. We love this program."

McInerney, who grew up spending long hours building Lego creations, still considers himself a kid at heart. And he hopes Buildup Mobile can someday branch out to host programs for children at other hospitals as well.

For now, he enjoys making play his work.

"I get to spend the day building Lego robots with kids," McInerney says. "You can't really beat that."

Photos by Bryan McCullough