Son calms mother after losing foot in lawnmower accident

When Keirsten Marsico saw her young son Joey for the first time after a lawnmower accident that required the amputation of his left foot, he told her everything would be OK.

“(After) he came out of the operating room that night, of course I was in tears and he just took my head in his hands and said, ‘Mommy, what’s wrong?'” Marsico tells PEOPLE. “I just said, ‘I’m really sad, buddy.'”

On Thursday, May 9, Joey, just weeks away from his fourth birthday, was watching his grandfather, Mark DeLuca, mowing the lawn in front of his family’s home in Whitehall, New York, when he made an innocent, split-second decision that put him in danger.

“He really loves tractors and mowing the lawn,” says Keirsten of her “active little boy,” the younger of her two children.

“He likes to help and he ran behind my dad who was on the riding lawnmower. And before my mom could reach him, my dad put the car in reverse and it all happened at once,” Keirsten recalls. “It was just – everything fell into place to make it happen.”

She continues: “It’s been hard for all of us, but my parents are just terrible and my dad is terrible.

According to the family, DeLuca quickly applied a tourniquet, which likely saved his grandson’s life. Joey was then flown by helicopter to Boston Children’s Hospital, where he underwent several surgeries on his foot, including an amputation.

During his difficult recovery, however, Joey was able to charm his nurses and doctors and impress his family and friends with his unusually mature attitude – not to mention his optimistic outlook.

“He’s a very strong boy,” says Keirsten, adding, “It’s almost like talking to a teenager. … He’s just very balanced.”

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His father Joseph says: “He has always been like this. He is very understanding and understands other people’s feelings and knows how to deal with things and other people. He is also very talkative. His vocabulary goes far beyond what he should be able to use.”

During Joey’s nearly month-long hospital stay, the Marsicos – who also have a six-year-old daughter, Gianna – shared responsibilities to help them adjust to the new normal.

“My daughter goes to school, so we try to give her some sort of routine,” says Keirsten. “She is autistic, so routine is very helpful for her. My husband and I agreed that maybe one of us should be home with her.”

Keirsten stayed home, “and never left Joey’s side,” she says of Joseph.

“When I left Joey the other day, I cried and he just did it again,” says Keirsten. “He wiped the tears from my eyes and said, ‘It’s okay, you don’t have to be sad.’ I said, ‘I know, but I hate leaving you.'”

Keirsten says the family’s Catholic faith – and the knowledge that this was a freak accident – helped them get through the experience.

“My biggest fear is that people will hear about this story and think, ‘Why didn’t they take care of him?’ Or, ‘How could they let this happen?’ And that’s honestly something I’ve thought about as his mother,” she admits.

But “I have to keep telling myself that this is all happening for a reason. God has a plan for this little boy, and it’s not something we understand right now, but this is his plan for him. Whether we understand it or not,” Keirsten says.

“So if someone else was in that situation, I would tell them it was an accident,” she says. “Accidents happen. We can’t control it and we don’t ask why because you’ll never know, you’ll just beat yourself up.”

“We just have to adapt and get over what’s happening,” she says. “And we just have to be there for him and stay together as a family.”

On June 5, Joey was released from the hospital and returned to his family almost a month after the accident. He turned 4 years old earlier this week.

His parents are encouraged by his progress – they say he will soon have a prosthetic limb – and marvel at how, despite everything, he has managed to express his feelings and reassure others.

“He was always just a special little guy,” says Joseph.