It seems becoming a first-time dad wasn't easy for John Krasinski!

In a new interview, the 36-year-old actor confessed he went through an "existential crisis" when he and his wife, Emily Blunt, welcomed their daughter, Hazel, in February 2014.

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John, Emily and Hazel in January 2015.

“I went through some really serious stuff. There is a mirror that is held up to me now. You have someone watching you. You have to lead by example. [I'm focusing on being] a better person every single day," The Office star told People.

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“I got to understand my parents better. I got to understand my wife better,” John said of becoming a father. “I got to understand how lucky I am to be in the fox hole with someone I can rely on 150 percent.”

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John and Emily in January 2013.

John also credits his 23-month-old child with positively affecting his acting career. “I had my daughter in February and then we shot [my new movie The Hollars] that April,” he said. “Those [few] months changed my life. They are the reason the movie is what it is.”

John and Emily, 32, first became an item in November 2008 and married in July 2010. The Devil Wears Prada actress previously dated singer Michael Bublé from 2005 until 2008.