"I was like, 'Yes!' and was in the mindset that I wanted to run a marathon, but obviously I couldn't do that," Wesolowski said. "I remember my mom saying, 'Kelly, you're so happy. This is the best mood you've been in for months,' and I said, 'Yeah, I am just so happy.' [Later during the run,] I was in my neighborhood, it was just starting to get dark out and it just felt so amazing."