rinn was diagnosed with stage three breast cancer while breastfeeding her 10-month-old daughter on September 1, 2021. From September to December 2021, she received six rounds of chemo. Her oncologist recommended exercise to reduce her treatment-related side effects, so she walked and hiked around the local conservation land, while carrying her daughter to keep her strong through treatment. In January 2022, Erinn had a double mastectomy and hiked to stay sane as she wasn't allowed to lift anything for six weeks, including her kids.

In March 2022, she started physical therapy, and 14 rounds of additional chemo and hormone suppression. It was a slow process and hard work, but Erinn persisted so she could feel strong enough to hold her kids. In May 2022, Erinn's physical therapist suggested she try distance running. Erinn always disliked distance running (or so she thought!), but she started slowly with 30 seconds running + three minutes of walking at a time. As it turns out, the advice to start running was magical; not only did running improve her physical health, but it also improved her mental health. From June to August 2022, Erinn slowly increased her runs to be able to run a whole mile, often while pushing her son in a stroller at night after her daughter had gone to sleep. His little voice would often ask for "one more lap around the neighborhood," which pushed Erinn to run a little further and grow a little stronger. He was her little coach.

In September 2022, during a run one day, Erinn had a wild idea and thought running a 10k (6.2 miles) to chemo would be cool. Much to her surprise and delight, her oncologist agreed! At this point in her running journey, Erinn could only run 2 miles consecutively, but this new goal to run to chemo gave her newfound motivation to further push herself. Erinn decided to make the run to chemo a small fundraiser for stage four breast cancer research, providing a reason to keep pushing herself despite being tired from chemo.

In November 2022, people started asking if they could run with Erinn, in-person or virtually, to her final chemo treatment. Immediately, Erinn said yes, but she went one step further and provided participants with race bibs and snacks. She coined the run the Chemo Day 10k Rainbow Soiree and on December 2, 2022, Erinn completed her run, which she officially named the Chemo Day 10k Rainbow Soiree. Her lifelong friend pushed her son in a jogging stroller most of the way, so Erinn could start and end the race with him - the same running coach who joined her on countless training runs leading up to that point. The nurses, staff and oncologists all came out to celebrate with Erinn at the finish.

In total, Erinn raised over $16,500 for METAvivor during her inaugural Chemo Day 10k, and she was joined by 19 in-person participants and 40 virtual participants from 13 states and two countries.