Lopilato announced the news via Instagram, sharing a black-and-white photo of her newborn daughter's hand.
“How to explain that our heart explodes with love? That there’s not enough hours in a day to think about it. I thank God for making us this gift of life and happiness! Because looking in her eyes is looking at heaven itself!” the Argentine actress wrote, in her native Spanish.
“We love you to infinity and beyond. We waited for you not only to grow as a family … you gave us light, hope, you are and will be our souls’ life."
Bublé and Lopilato are also parents to sons Elias, 2½, and Noah, who turns five in August, who diagnosed with cancer in 2016.
The 'Feeling Good' singer will perform in Sydney in October this year for a one-off Australian show.