Jack Jo...
Justin Bieber, Maroon 5 and Keith Urban are among the singing stars who have recorded versions of Happy Birthday for a new cancer awareness campaign.
Jack Johnson, punk band Devo and country singer Colbie Caillat have also added their vocals to the American Cancer Society's latest initiative, according to CMT.com.
The project is designed to call attention to the 11 million survivors of the disease who celebrate their birthday each year, giving hope to sufferers.
