In a heartbreaking Facebook post on Friday, Canadian singer Michael Bubble revealed that his elder son Noah had been diagnosed with cancer and was rushed to the US for treatment. Shortly after the devastated parents broke the news, prayers came pouring in from fans and celebrities and according to a recent report, the couple seems to be "hopeful" as the three-year-old's battle with cancer begins.

"They are really sad but hopeful," a source told Us Weekly about the gruelling journey that lies ahead for the singer-model couple. "They immediately got him very good care and they are hoping and praying for the best. They are getting him the best doctors around. It's really heartbreaking. This was a real shock, but they are doing everything they can," the source added.

The Grammy-winning singer had revealed on Facebook that both he and his wife Luisana Lopilato have put their careers on hold over concerns about their son's health. The 41-year-old Feeling Good hit-maker also pleaded for privacy during this difficult time in their lives.

"We are devastated about the recent cancer diagnosis of our oldest son Noah who is currently undergoing treatment in the US. We have always been very vocal about the importance of family and the love we have for our children," Buble had announced earlier.

Can't believe my little man is 3 years old today !! Happy birthday Noah /Spider-Man. Feliz cumpleaños ! Your mommy And I love you so much ! #loveofmylife #proud #papa

A photo posted by Michael Bublé (@michaelbuble) on

As young Noah begins his battle with cancer, another source told the magazine that Buble and Lopilato are "staying positive and Noah is a fighter." The parents have been "inundated with kind wishes today, and that's really helping", the source continued.

Buble tied the knot with the Argentine actress in 2011 and the couple welcomed their first baby in August 2013. The singer and Lopilato are also parents to nine-month-old Eli. Speaking about his children, the singer-songwriter had earlier told the magazine, "The boys are good. They make each other laugh. It is a beautiful feeling."

"[I] just pray that everything stays good and they are happy and healthy and all of that," he added.