Baby Harper joins two-and-a-half-year-old sister Hannah Kathryn.
Hader is also celebrating being nominated for a Primetime Emmy Award in the Outstanding Supporting Actor in a Comedy Series category.
The comedic actor, 34, admits his wife Maggie is better at parenting than him, knowing how to stay calm in scary situations with their child.
Hader said, “[When Hannah] hit her head for the first time, she had that pause moment where she looks at you and my wife is really good because she’s like, ‘Ohh, yay, it’s okay'”, but Bill said, “She hit her head and I’m like, ‘NOOOO!’ And she’s like, ‘Wahhh!’ My wife [said], ‘Give her to me, just give her to me!'”
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