Motherwell boy Caden was just six when he died last month after a four-week battle against meningococcal septicaemia.
His parents David, 44, and Angela, 39, and brothers Declan, 12, and Ethan, 3, launched a Facebook page to tell of his illness. It drew support from more than 50,000 people around the world.
The song, which David wrote, is called Caden's song (My First Christmas). Proceeds will go to the York-hill Children's Foundation which has established a tribute fund in Caden's memory.
David is joined on the recording by Union State – a band made up of family and friends including singer-songwriter JJ Gilmour of The Silencers, Wet Wet Wet star Graeme Duffin and composer David Lyon.
The song was prod-uced by Sandy Jones and David Beggan at the Foundry Music Lab, which donated the cost of the studio time.
David said: "Angela, Declan and Ethan and I are in mourning for Caden and it has been a really difficult time.
"We miss him more than we can say. We wanted to say thank you to Yorkhill Hospital and all of the medical teams there especially the 'Blue Angels' who were so compass-ionate to Caden and ourselves."
Chief executive Shona Cardle said Yorkhill Children's Foundation was "honoured" by the gesture.
The song, can be download on iTunes via the link http://bit.ly/ SXR369
Caden's school, Ladywell Primary in Motherwell, is donating its Christmas song's proceeds to Meningitis Research Fund.