Last summer, Chrissy Teigen and John Legend got a call that would change the life of their family forever. It was from the football day camp of their son Miles, 6, informing them that there had been a breakout of shigella—a bacteria that causes intestinal illness—and that he was being sent home.

But after a couple of days, it was apparent that something else was wrong. Miles was “doubled over in pain,” unlike any of his peers. They took him to the ER, positive that it was his appendix.

Three days and many blood tests later, though, doctors offered the family a diagnosis they never saw coming: Miles had Type 1 diabetes (T1D).

“It was just so shocking,” Teigen tells Fortune.

Unlike Type 2 diabetes, often linked to lifestyle factors including diet and exercise, T1D—formerly known as juvenile diabetes—is an autoimmune condition. It occurs when the immune system mistakenly attacks insulin-producing cells in the pancreas, making it impossible for the body to regulate blood sugar without insulin therapy.

“All of a sudden we were just thrown into having to learn everything imaginable the same day that he needed to start [insulin] shots,” Teigen recounts. “It was just crazy, that first week of, you know, driving to Children’s Hospital, practicing [injections] on different fruits, practicing on yourself, trying to feel like what the devices would feel like on yourself.”

The devices she refers to are a glucose monitor and insulin pump, which Miles now has to always wear. “And he’s a bean pole,” she says. “He’s a skinny little dude! And they’re big. The pump is like a battery pack hanging off your arm all the time.”

She admits she didn’t know quite how difficult it would be. “I was like, Oh, this is gonna be fine. I had T1D friends when I was little… Every once in a while they had to prick their finger or then they’d get a Starburst. Like, I had no clue what it would be like for him.”

Chrissy Teigen playing outside with her son Miles

And getting used to the new routines has come with a steep learning curve, shares the mom of four: Miles; Luna, 8; Esti, 2 1/2; and Wren, 2. Especially since Legend is typically the one in charge of preparing the insulin.

“John’s out of town. I had to FaceTime with him yesterday just to make sure I was doing it right, because it’s like, you don’t want to get this wrong,” she says. “It’s a process, making sure his kit is ready all the time, constantly being really alert and having to have those emergency alerts on your phone for the devices. It’s really all-encompassing.”

Adjusting to the new reality

While the initial news of the T1D felt like a “gut punch,” she says she soon came to realize that “if anybody could do this, it would be Miles, and if any family could rally around him, it would be us.”

That’s because Miles is a roll-with-the-punches kind of kid. “Miles is our crazy, wacky 6-year-old. He’s bananas. He is all over the place. He eats what he wants. He’s a chicken-nugget kid. He is carb-loading. He doesn’t eat vegetables,” she says.

Their daughter Luna, on the other hand, is “incredibly empathetic to the plights of anybody, to whatever anybody is going through—any human being, any animal.” And that includes her brother and his new medical needs.

“If the roles were switched, I’m not sure Miles would be able to be that way to Luna,” Teigen says. “I’m not sure Luna would be able to be as strong with it as Miles is.”

But when it comes to speaking out about the situation in order to raise awareness and potentially help others, Miles is all in, she says. And it’s something Teigen and her son have signed on to do for Sanofi, as spokespeople for its Screen for Type 1 movement, which encourages people to get screened for T1D. Screening can be done through a simple blood test which, when taken before symptoms appear, can allow people to prepare for symptoms and treatment before they need insulin or are in life-threatening situations.

“If we could have screened earlier—if we would have had just a week’s notice, a year’s notice, that would have been amazing. It would have changed the game for us completely,” she says. So that’s why we’re really advocating for people to talk to their doctor about screening for Type 1.”

But now, as spokespeople, she says, “it means the world to us to be able to tell [Miles] that he gets to be this person for other people to look up to. He’s the kind of kid that thrives off that and really loves that and is really proud of it.”

It’s a quality he likely gets from his mom, who has been sharing honestly about everything from parenting challenges to medical issues on her social media for many years. “I always try to live very authentically online,” she has said.

While they’ve yet to discuss Miles’s new diagnosis with Usher—a fellow Sanofi spokesperson, whose son was diagnosed with T1D at the age of 6—they did find some inspiration from Nick Jonas, Legend’s former fellow judge on NBC’s The Voice, who has lived with T1D since he was 13. Teigen says they ran into the pop star at the Paris Olympics shortly after Miles received his diagnosis.

“He had his device on,” she says. “And so for Miles to get to talk to him and see his devices was so cool because Miles is obviously a huge fan of music and watches John on The Voice every chance he gets—and he was so amazed that that Nick was there, and that Nick has [T1D].” Every time Miles sees someone with a device, she adds, “he’s like, so amazed by what they’re doing, what they’re able to still do, which is awesome.”

More about preventative care:

Why Chrissy Teigen is speaking out about her 6-year-old’s Type 1 diabetes diagnosis