Alyson Hannigan, How I Met Your Mother Alyson Hannigan, How I Met Your Mother

Lily's father is coming to How I Met Your Mother, series creator Carter Bays tells TVGuide.com exclusively.

"We're going to meet Lily's dad later in the season. He hasn't been cast yet," Bays says. "It will sort of explain a lot about Lily: why she is the way she is, why she's kind of a control freak."

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