The 38-year-old actor announced Friday that wife Kelsey Porter gave birth to a daughter.
"Sweet dreams, world," he captioned a photo on Instagram that showed the baby girl lying on top of him.
Porter and Kelsey are already parents to 2-year-old son McCoy Lee. The couple announced Kelsey's second pregnancy in April, and confirmed in July that they were expecting a daughter.
"Our baby girl is going to have a tough time deciding who to cheer for...but we'll love her no matter what school she chooses...right, @kiwiporter," Porter, a Nebraska Cornhuskers fan, wrote at the time.
Porter and Kelsey told People after McCoy's birth that they had used in vitro fertilization to conceive their son.
The couple wanted to ensure a healthy child after Kelsey was diagnosed with Huntington's disease.
"She figured out how we could have a child without passing Huntington's disease," Porter told the magazine.
"Because I have Huntington's any child we have has 50/50 chance of having it, so to eliminate that, we did in vitro fertilization," Kelsey explained. "We did preimplantation genetic diagnosis ... They tested all our embryos for Huntington's."
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