The decorated Olympian and his wife, model and volleyball professional Morgan Beck, welcomed a son early Monday morning (18May15), and the new mum took to to share the happy news.

The first photo of the tot features him sleeping on Beck's chest, and she wrote, "Welcomed our little man into the world at 12:35 am this morning. 7 lbs 13 ounces and 20 inches of pure love!"

She shared another photo of Miller snuggling up to his new son, and Beck added, "Daddy loves his baby boy. Melts my heart. I'm the luckiest girl in the world."

The baby boy is the third child for Miller, who has a six-year-old daughter and one-year-old son from previous relationships.

Miller and Beck wed in October 2012, and just two months later, announced they were expecting their first child. Beck revealed she miscarried the baby at the beginning of 2013.