The actress will be playing a pregnant ER paediatrician named Lilly Manning in NBC's upcoming Chicago Med, reported Deadline.
Showrunner Andrew Dettmann dropped hints about the character, saying that she is slightly overwhelmed by the prospect of having her first child.
"When we meet her, she's very pregnant. She's just a really sweet, warm, midwest woman who planned it out, studied, worked hard, got everything to where she wanted - the husband and everything going the way it's supposed to be going.
"But this is her first child, and it seems to me at the end of the day there's a little bit of denial about the fact that she's about to undergo an enormous change in her life."
However, Laurie Holden recently pulled out due to "family reasons".
Besides, "Pretty Little Liars", DeVitto has appeared in "The Vampire Diaries" and "One Tree Hill".