The family of a young girl in desperate need of a heart transplant will spend their second Christmas away from home waiting on a life-saving call.

Young McKayla Warder has hypoplastic left heart syndrome, a birth defect that affects normal blood flow through the heart.

Her devoted family, from Windsor, Ont., has spent years, on-and-off, at Toronto’s Ronald McDonald House.

The seven-year-old’s heart is failing and enlarged. The Warders are on standby waiting for a call from the nearby Hospital for Sick Children that a donor has been found.

“She can't walk and she can't talk but she is striving every day doing more and more than what the doctors didn't think she would be able to do,” McKayla’s mom Rejeanne Warder told CTV Toronto.

McKayla has defied expectations since before she was born, undergoing an experimental surgery while still in the womb. She was given a less than 1 per cent chance of surviving birth.

Since she was an infant, the eternally happy girl has endured numerous surgeries and health struggles.

And as the painstaking wait continues, life goes on with dad Justin Warder working in Windsor during the week and returning to Toronto on weekends.

Judy Noordermeer, a spokesperson from the Ronald McDonald House, said the Warders have become part of the heart and soul of many of the other families who have stayed there.

“It feels like forever. We've been away from home for a very long time,” McKayla’s father said.

Her mother credited their faith with helping her family stay positive.

“Being together, making every memory, every occasion, every holiday count, is a blessing, is the biggest gift,” she said.

To support McKayla and her family at Ronald McDonald House you can click here.