Speaking to Argentinian talk show host Susan Gimenez, Lopilato said in Spanish, "Thank God, the worst is now over, but this is a long and ongoing process. It's devastating for any parent to receive the news we did."
Bublé, 41, and Lopilato, 30, confirmed last November that their eldest child, Noah, now 3, had been diagnosed with cancer and was receiving treatment in the United States. Both parents announced that they'd put their careers on hold to be able to devote more attention to the boy.
"When they did the ultrasound, I was told they found something in his belly," she recalled. "That day I made the decision to take a flight [to Los Angeles]."
As soon as the singer received the news, he met his wife and son in California, she said, and they spent the next seven months at Noah's bedside. During their time in the hospital, she said, people dressed in superhero costumes came by to cheer the boy up.
"These things make you realize that the most important thing is to have faith and to be strong," Lopilato said. "There was no week when I did not go to church ... There is not one single night in which I don’t go to bed asking God, ‘Please!’”
In June, Bublé made his first public appearance since Noah's diagnosis, appearing in Ottawa, Canada, to receive a prestigious award.
At the ceremony, he said of his family, "There are no words to describe how I feel about you. Sometimes, 'I love you' just isn't enough because what I feel is just so much more."
Bublé and Lopilato, who wed in 2011, also have a 1-year-old son, Elias.