The couple announced they were expecting in April (13), less than a year after their wedding in June last year (12), and they are now celebrating with baby boy Wyatt Oliver, who weighed in at a healthy nine pounds, eight ounces (4.2 kilograms).
Olsen tells People.com, "I've been a part of some pretty incredible experiences in my life, but I've never been a part of something so surreal, so life affirming and so insanely beautiful as watching my son come into this world. It was this watershed moment where I knew that everything I valued before seems finite and temporary."
The actor also revealed his wife had opted for a home birth, adding, "Sarah wanted to do a natural birth at home and she fought through 17 hours of intense labour before we finally got to meet Wyatt. I can only take stock in how lucky I am to have this amazing, powerful woman in my life, and a beautiful new son."