Maddox was born on Easter Sunday after the pregnancy was first announced on Dancing With the Stars back in October. Holker is a professional dancer for the ABC reality competition show.
This marks the first child for the couple, who tied the knot in December 2013. Holker has a 7-year-old daughter, Weslie, from a previous relationship.
"He has a big, full head of hair," Boss gushed about his newborn. "We don't know which way it lies just yet so that's going to be interesting, but I'm just so proud of him for every little thing he does. From hiccuping to sneezing to waking up from his sleep -- everything is just amazing. It really is."