Ellie Kemper's son only calms down when he sees Allison Williams' face

May 26 (UPI) -- Ellie Kemper detailed on Late Night with Seth Meyers Thursday how Allison Williams' face is the only thing that will calm down her 10-month-old son James.

"James is a spirited child," the Unbreakable Kimmy Schmidt star said to Meyers about how her son was cranky while on a flight to Los Angeles.

"I was showing him like the seat belt buckle and like, the barf bag," she continued of how she tried to make her baby happy.

"Nothing would appease him until I noticed the airline magazine, the cover of the magazine was the beautiful face of Allison Williams. Her gorgeous face delighted my child. It was the only thing that worked," Kemper said. "We were like, flipping through the magazine, there were like ads for shoes, James would not smile, and then her face would come on again and he just lit up."

Now the 37-year-old says she keeps photos of Williams around the house just in case he begins to act up again. "It's worked many times," she said. "It's the best baby trick. Allison Williams is the baby whisperer."

Kemper also shared photos with the late night host of James appearing happy alongside a magazine cover featuring the Girls star and then crying when placed near a book.

Kemper welcomed James, her first child with husband Michael Koman in August.