Cameron Gallagher and her best friend Abby Donelson ran and finished the race together.
"I went to hug her," Donelson says. "We were walking away with our arms around each other and she said like 'I'm going to pass out.' And then she just kind of went down."
Gallagher collapsed and was taken to the hospital where she later died. Her parents, who were by her side, say they think her death was cardiac related.
Friends and family say Gallagher was an inspiration for their family and was full of life.
"She just loved people," Donelson says. "And she was very fun to be around and crazy. She really was just a genuine person and she really wanted to make a difference."
"She set a goal and completed it with a smile as she did with so many accomplishments in her short life," they say. "The entire community has been so supportive and we are so thankful for your prayers and thoughts. Please use Cameron's story as an inspiration to set goals, overcome obstacles and fight the good fight. She did that every day. We love you so Cameron."
Gallagher was a sophomore at Douglas Freeman High School. She had transferred after doing a year at St. Gertrude's.
One of the things Gallagher was organizing was a 5k to raise awareness about suicide. Her friends say now the race will be in her honor. For more information, go to facebook.com/speakup5k.