She’s running Boston in memory of her 3-year-old patient

Boston Marathon

Sammie Taylor, a nurse at Boston Children’s Hospital, is running for Demi Costa, who died from rare disease APLAID earlier this year.

By Kelly Chan

April 3, 2025 | 6:00 PM

1 minute to read

In our “Why I’m Running” series, Boston Marathon athletes share what’s inspiring them to make the 26.2-mile trek from Hopkinton to Boston. Looking for more race day content? Sign up for Boston.com’s pop-up Boston Marathon newsletter.

Name: Sammie Taylor
Age: 31
City/State: Hanover, Mass.

As a registered nurse in the acute cardiac care unit at Boston Children’s Hospital, I have the privilege of caring for the strongest, bravest little heart warriors. This year, I am honored to run the Boston Marathon in memory of one of my beloved patients, Demi Costa.

Born at 37 weeks and just 5 lbs., Demi faced challenges from the start. At only three days old, she was med-flighted to BCH after an IV complication resulted in the loss of all her fingertips on her left hand. By her first birthday, she had been hospitalized multiple times, ultimately leading to a rare and life-threatening diagnosis: APLAID.

Demi had the most severe case of APLAID ever documented in the country. This genetic disorder impacted every part of her body—chronic lung disease, focal seizures, one functioning kidney, cardiac procedures, chemotherapy, immunosuppressants—the list goes on. She endured it all with unmatched strength, including an 11-week hospitalization following open-heart surgery this past summer.

With no treatment options left, Demi needed a bone marrow transplant. On Nov. 27, 2024, she received her second chance at life — her “rebirthday”—with her father, Jon, as her donor. She fought with unimaginable courage, inspiring everyone around her.

On Jan. 13, 2025, with the heaviest of hearts, we said goodbye to Demi. Though she is no longer physically with us, her joy, sass, and warrior spirit will live on forever. She was a light in this world — mischievous, hilarious, and full of love.

I am running this race not only for Demi but for all children who face unimaginable battles with unwavering strength. Every step I take is for her. Demi’s fight may be over, but her legacy will never fade.

Editor’s note: This entry may have been lightly edited for clarity or grammar.