A 5-year-old boy from Milford is recovering at home after being diagnosed with a rare, coronavirus-related condition.

Jace Bruno spent four days at Yale New Haven Hospital being treated for an uncommon, and sometimes deadly, illness linked to COVID-19 in children.

It's called Multisystem Inflammatory Syndrome or MIS-C.

"It basically causes inflammation internally throughout the body, it affects all your organs," says Kendall Bruno, Jace's mother.

Kendall Bruno worried Jace might have MIS-C when he suddenly spiked a fever last week.

He'd had a mild case of COVID-19 four weeks earlier but quickly recovered.

"We took him to the doctor Thursday because his fever was getting higher; it was at about 104. They said that it was probably just a virus and to give him Tylenol, Motrin - just keep an eye on him," says Kendall Bruno.

She thought it was something more. Jace's fever continued to rise, and on Saturday, he had more symptoms.

"I said to my husband, 'I'm not taking a chance on this, I'm taking him to the hospital,'" says Kendall Bruno. "And by the time we were admitted, his temp was at 105.3, he was not really responsive, he was shaking. He just really wasn't doing well."

But doctors at Yale knew what to do. His fever was gone the next morning, and each day he improved.

Jace couldn't have visitors but a friend did send him a giant Mickey balloon, which was dressed as a superhero.

"He took the mask and cape off and put it on himself and wore it out of the hospital, literally ran out of the hospital when we left," says Kendall Bruno.

Jace's mother says he's always been her superhero - and his recovery is now another reason why. Still, she says he's still not fully back to normal.

He's on steroids for the next six weeks and will continue seeing a cardiologist and rheumatologist at a special clinic for MIS-C at Yale. Kendall Bruno is reminding parents to trust their instincts.

The CDC says there have been 3,185 cases of MIS-C in the country and 36 deaths. Symptoms of MIS-C include fever, stomach problems, skin rashes, and eye and mouth inflammation.

Doctors say there may be a genetic pre-disposition to MIS-C. Jace is taking part in a research study.