The already-sprawling cast of "This Is Us" is growing in season three, with sitcom vet Jane Kaczmarek landing a guest spot on the NBC drama.

Kaczmarek, the Emmy-nominated star of family comedy "Malcolm in the Middle," is set to appear in an upcoming episode of "This Is Us," according to Entertainment Weekly. It's currently unclear how -- or during what time period -- her character will factor into the show, but EW reports that the role is of "a liberal university professor and scientist who is described as intelligent, warm, and down-to-earth."

As EW notes, she's just the latest famous family matriarch from a beloved sitcom to appear on the NBC tearjerker, following Katey Sagal ("Married... With Children," "Eight Simple Rules") in season one and Debra Jo Rupp ("That '70s Show") in season two. Fingers crossed that they can somehow find a way to include Jo Marie Payton -- a.k.a. Harriette Winslow from "Family Matters" -- in an upcoming storyline.

Season three of "This Is Us" is set to focus heavily on Jack's (Milo Ventimiglia) time in Vietnam, as well as provide some more background on Pearson spouses Beth (Susan Kelechi Watson) and Toby (Chris Sullivan). Creator Dan Fogelman has called this third outing the show's most ambitious season yet, and we can't wait to see it all unfold.

"This Is Us" is set to return to NBC on September 25.

[via: Entertainment Weekly]