The waiting game continues on Sunday's episode of NCIS: Los Angeles, with Deeks (Eric Christian Olsen) and the rest of the team anxiously hoping for Kensi (Daniela Ruah) to emerge from her coma. And Deeks' confidence is starting to wane.

Deeks' mom (Pamela Reed) is in town to help him through the crisis, and while she has a much more optimistic take on the situation, her presence may not be completely comforting to Deeks.

"People handle these types of catastrophic events differently," Olsen tells TVGuide.com. "To complicate things further, his mom ... is kind of a belligerent 4-year-old in her inability to accept the circumstances. ... She's being mean to the nurses and yelling at the doctors and smoking."

NCIS: LA: How long will it be before Kensi wakes up?

So Deeks turns to a different source. In this sneak peek from Sunday's episode, Deeks has a heart-to-heart with Hetty (Linda Hunt) in which he wonders whether he has what it takes to nurse Kensi back to health, not knowing what condition she'll be in when she wakes up — if she wakes up at all.

"You see also why Deeks needs Hetty, because in these times in which things become so turbulent, you see Hetty becomes calmer and you see [Deeks'] mom become more of a child," Olsen says. "Which is why he goes to Hetty for advice and why he ends up kind of babysitting his mom. I think it's another great window into the role that these two women play in his life."

Check out the video to get Hetty's take on the situation.

NCIS: LA airs Sundays at 8/7c on CBS.

(Full disclosure: TVGuide.com is owned by CBS.)