Flags flew at half-mast Thursday across Cambridge as an entire city mourned the passing of Kayla Baker.

The 15-year-old St. Benedict Catholic Secondary School student had been at SickKids Hospital in Toronto since last March, when she was admitted for a lung transplant following a two-year wait.

Over those nine months, her story – and her limitless advocacy for organ donor registration – captivated people in Cambridge and beyond.

In her hometown, green ribbons sprung up on lampposts, benches and trees as a show of support.

A ‘Run-a-Lung’ fundraiser was held in the spring to raise money for the SickKids rehab centre, with Kayla rolling through the hospital’s halls as hundreds walked and ran in Cambridge.

Thursday morning, Kayla’s mother, Susan Tremblett, posted on Facebook that her daughter’s “fight had come to an end” late Wednesday night, as she was surrounded by family and friends.

“My kayla was a strong young lady even when she was told that she would not go home she still got up and planned for the day, did rehab, asked what are we going to cook today and when can I go for a walk to get out of the room,” she wrote.

“Thank you from the bottom of our hearts for your support and making the best Christmas for her with all of the well wishes and presents.”

Family friend Sarah Taylor spoke to CTV News about Kayla’s life and legacy Thursday on behalf of her family.

“The family would definitely like to thank everybody for their support,” she said.

“They simply asked me to be here because they need time. They need time to be a family.”

Taylor praised Kayla’s tireless efforts to raise awareness of organ donation – and the selflessness she displayed in all other facets of her life, even while in hospital.

“She would read a story about a dog that was lost or a family that didn’t have anything for Christmas and would want to know how she could help,” she said.

Between 2010 and 2013, organ donor registration rates rose seven per cent in Waterloo Region as a whole and nine per cent in Cambridge specifically – increases Taylor attributes in part to Kayla.

Carol Dubeau, a double lung transplant recipient who has known Kayla for several years, says – in words many others echo – that even from a young age, Kayla was wise and mature beyond her years.

“You never felt like you were talking to a child,” she said.

“She knew the statistics, and they weren’t good – however, she was going to do everything that she could possibly do so that others didn’t have to go through what she went through.”

Another Run-a-Lung fundraiser is being planned for this spring.