Tommy Kelly is four years old. This week, the rest of his kindergarten classmates from Saint John Paul II Catholic Academy in Neponset are where they should be: enjoying their first full days of summer vacation at the sands of Tenean and Nantasket or planning for a week or two down the Cape with their families.

Tommy has just returned home after a grueling three-week stint in the hospital, where he’ll probably spend a good stretch of his summer as well.

Earlier in June, Tommy fell violently ill. His parents – Katy and Eddie Kelly – rushed him to Children’s Hospital. Within a day or so they were given the diagnosis: Their boy has cancer in his kidneys. Stage four. It may have spread beyond there. He needs surgery— and maybe chemo or other aggressive treatments— to save his life.

It is impossible to overstate the wave of shock and compassion that swept through Neponset – and then across the wider Boston community – as the news was shared over the weekend. Eddie, who has become a national champion of union firefighters, grew up in the shadow of St. Ann’s brick tower on Neponset Avenue. His mom, Katy, is a legend in her own right – most recently for her selfless dedication to Team MR8, the marathon squad that has raised over $1.25 million for the Martin W. Richard Foundation. The Kellys are deeply respected, the consummate Boston Irish family whose life revolves around service to God, country, neighbors.

Last Tuesday, the tight-knit St. Ann’s parish community gathered to rally around Kate and Eddie and young Tommy. An overflow crowd packed the pews of the church to pray the rosary on the eve of Tommy’s first operation. The post-operation news, Eddie later shared to his friends on social media, was mixed. The kind of tumor Tommy had was treatable, the doctors think. But it was not something they could simply remove. They’ll need to get more tests back— and Tommy will very likely need radiation treatment to shrink the cancer.

It is all enough to lay low the mightiest men and women, let alone a little boy. But the Kellys, as many have noted in thousands and thousands of posts online, are made of the toughest stock imaginable. The most common sentiment— “If anyone can beat this, it’s a Kelly”— might sound like a trite slogan. It’s anything but in this case.

The Kellys’ story has gone viral, particularly among the huge network of America’s firefighting and law enforcement communities. Firehouses in New York City and Texas and all around the country have sent along heart-felt salutes to Tommy: Some have added him to their daily roster boards or voted to make him an honorary member of their department. A Facebook page dedicated to Tommy – “Fight Like TK” – is lit up around the clock with prayers, photos, and signs of support.

Edzo Kelly has been keeping everyone up to speed on his son’s battle from day one via Facebook. Last week, she shared some good news. Testing has confirmed what they’d hoped for: Tommy’s tumor is a kind that can be removed in many cases. A few days later, he reported, Tommy was back in his own bed at home in Dorchester.

“We are coming into a period where Tommy’s treatment has made him susceptible to viruses and infection, so the Docs have asked us to limit contact and have positively no contact with anyone who may be sick. So don’t take offense if we see you out and about but just wave hello,” Eddie wrote. “Being a tough little guy, Tommy doesn’t appreciate sympathy. He just wants to be treated like any other rambunctious soon to be 5 year old. Which is refreshing! Thank you for your prayers, they are working! Please keep them coming for all sick kids here and everywhere!”

“We will forever be grateful for the support we have received from around the world and our own Parish!”

It’ll be a tough summer for Tommy Kelly and his clan— including his big sister. But it’s times like these that remind us why we live here. Our community stands tall and supports its own. Tommy Kelly and his family knew that already, better than most in fact. Right now, it’s time to show them that we get it, too.