Michael Buble's 3 Year Old Son Has Cancer

Michael Bublé and his wife are confirming their toddler, Noah, is getting treatment for cancer.

Michael and Luisana said they were devastated by his recent diagnosis and would be "suspending professional activities for now" to focus their time and attention on the 3-year-old.

According to reports in Argentina, where the family lives, doctors initially thought Noah had mumps ... but when they brought him to see doctors in the U.S. ... they found the cancer.

In their Facebook post Friday morning, Michael and Luisana wrote ... "We have a long road ahead of us and we hope that with the support of our family, friends, fans around the world and faith in God, we can win this battle."