One of those kids was nine-year-old Genevieve Koropatkin, who loved to run.
On Saturday morning, Girls on the Run of Greater Connecticut hosted a 5K in memory of her and her three brothers: Archer, 5; Benjamin, 7; and Lukas, 11.
"She really thought that the program was so important," said Johanna Rincon, executive director of GOTR. "So, we're so happy that her friends and family are here to support, everybody who is here, and we miss her so much."
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Rincon says more than 600 girls from around the state participated in this event, including schools and teams from Darien, New Haven, Seymour, and Windsor.
"I've received a number of emails because every girl has been changed. Every girl has pulled something, has learned something from this," said Jessica Soule, of Enfield.
Soule is the head coach for the Girls on the Run team at Prudence Crandall Elementary school in Enfield. She and the assistant coach, Stepanie Tullock, meet with students twice a week to train them.
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"I just love the fact that we have built their confidence. Then to have this event and see them go through this. It's just awesome," said Tullock.
Some of students said this was their very first 5K.
"I'm really excited for this. We've been training," said Sophia Gemme, of Enfield.
NBC Connecticut's Caitlin Burchill emceed this inspiring event. Runners we spoke to say the organization has inspired them in many ways.
"It teaches really about positivity and our self-care," said Cecila Tuttle, of Enfield.
"It teaches you to just keep going," said Gemme. "Like pretend you have an envelope and every time you get to that envelope, you just keep pushing it because you have to try. There's no limit in life and you just have to try your best, and live life the way it's supposed to be lived."