‘Grey’s Anatomy’ Expected To Introduce Fourth Shepherd Sister

Patrick Dempsey arriving at the World premiere of 'Bridget Jones's Baby' at Odeon Leicester Square.
Gareth Cattermole / Getty Images

Patrick Dempsey landed the role of Dr. Derek Shepherd on ABC’s Grey’s Anatomy in 2005 and kept the role until his character’s tragic death in Season 11. During his time at the hospital, viewers learned quite a bit about the hunky doctor’s backstory, including the fact that he had four sisters who were all doctors. As the show went on, viewers were introduced to three of Derek’s sisters, Amelia, played by Caterina Scorsone, Liz, played by Neve Campbell, and Nancy, played by Embeth Davidtz, but the fourth sister has been elusive, until now.

According to a report from Entertainment Weekly, the folks in charge of casting for Grey’s Anatomy are currently looking for an actress to play Kathleen, Derek’s fourth sister. As of right now, not too much is know about Kathleen beyond the fact that she’s a psychiatrist. The character will be introduced in a Season 15 episode that will reportedly revolve around Amelia, who has become the replacement in-house Shepherd sibling.

After ABC announced its decision to expand the season from 22 episodes to 25 episodes, showrunner Krista Vernoff knew she wanted to use one of those bonus episodes to dive deeper into Amelia’s story.

“I had an extra standalone episode idea that I wanted to do this season,” she told TV Line. “So it doesn’t really lengthen our season too much. It allows us to tell [this Amelia-centric] story that we might not otherwise have gotten to tell this season.”

As for the actress that will be bringing the story to life, Scorsone says she’s nervous but optimistic.

“I’ve been doing the show for a long time and just hearing what it about fills me with nervous excitement,” the actress said. “It’s not just, ‘Let’s follow Amelia to the neuro lab’ it’s definitely a little standalone. It’s almost like a little movie on its own.”

In the trailer for next week’s episode, Amelia and boyfriend Owen are facing quite a bit of uncertainty. Amelia recently took in a teenager struggling with a drug addiction and her newborn son, who Owen decided to adopt. However, when the teen ends up in rehab, her parents come looking for their grandson and it’s possible they might take the child away from Owen and Amelia.

Owen is also expecting a child with his best friend, Teddy, and the two have been sharing subtle, but tender moments together in recent episodes. It’s possible that Owen and Teddy could rekindle their old relationship leaving Amelia out in the cold.

Fans will just have to wait and see how the story unfolds for their favorite characters.

Grey’s Anatomy airs on Thursdays at 8 p.m. on ABC.