The engaged couple welcomed a baby boy, Asher James Mooney, on Monday (24Jan17).

"It's hard to describe the love you feel for the first time when you hold your child," the 25-year-old country singer wrote on Instagram beneath a photo of himself, his fiancee and their newborn in the hospital.

"I will never be the same. Asher James, I promise to be the father you deserve. And Hannah, I promise to be the husband you want and need. I love you both so much. You've given me everything I never knew I needed. Welcome to the world Asher James Mooney."

Mooney proposed to the former Miss Arkansas USA in August (16), a year after they began dating.