By Juli McDonald

FREMONT, NH (CBS) – Jane Pellegrini cries out of relief. Out of overwhelming love for her brave boy – her Joey – who just gave them the scare of their lives.

“I’m just so happy to be home. So grateful that I am home, and my son is home,” Pellegrini said.

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A month ago, the first week of October, the 9-year-old tested positive for COVID-19. But he was mostly himself.

“It’s rare. It doesn’t mean it’s going to happen. But it can clearly. It did for us,” the Fremont, New Hampshire mother said.

“He had very mild head cold symptoms. Just nose congestion, no fever, no respiratory. Nothing,” the mother recalled.

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His bout with COVID seemed like no big deal. Until Halloween, when the mother and son went first to urgent care in New Hampshire and were then rushed to Mass General. Joey had Multisystem Inflammatory Syndrome, affecting his heart.

“Symptoms usually present 3-6 weeks post COVID. It often looks like a stomach bug with vomiting, diarrhea, fever,” Pellegrini has learned. “At one point his heartbeat was so fast he was visibly shaking; Almost like vibrating,” she remembers.

After a week in the pediatric ICU, Joey and mom were back home Friday night. He’s safe and better, but he’ll be closely monitored. The long-term effects are unknown.

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“A lot of things here I couldn’t have fathomed a week ago when my child was a normal healthy kid. Just really grateful, and happy to be home with my family,” she said.

Juli McDonald