9-1-1's Peter Krause breaks down that emotional rescue — and teases what's up with Jonah

Warning: This article contains spoilers for Monday's episode of 9-1-1, "May Day."

After losing his wife and kids in a fire he started, Bobby Nash is being called "Dad" again.

The 9-1-1 fire captain (played by Peter Krause) literally walked through fire to save his stepdaughter May (Corinne Massiah), a rescue that culminated in May removing any "step-" from their relationship.

"I think that there is a part of Bobby that thinks that he does not deserve to be a part of this family. But he looks at May like his daughter, not just his stepdaughter," Krause tells EW. "He's very respectful of Athena [Angela Bassett] and Michael [Rockmund Dunbar] being May and Harry's [Marcanthonee Reis] parents, but he definitely feels responsible for them. Getting to play that commitment that Bobby has to make sure that nothing is going to happen to May really helped me drive this episode."

"I think this was kind of a redemption moment to save his kid after he lost his family and he has definitely adopted May as his own daughter and May has adopted him as her second dad. There has been an unbreakable bond made," adds Massiah, who also reflects on the death of Claudette (Vanessa Estelle Williams): "May and Claudette had just worked through their differences and it was just stripped away in a blink of eye. To see Claudette die after May tried so hard to save both of them is really going to her hit hard."

Krause says that while Bobby may not be very vocal with his grief, "he's more quietly driven now to protect everybody around him and everybody in his life — everyone at the firehouse and all of Athena's family. I think because of his past and losing his family, he feels incredibly, especially protective of May and Harry."

Bobby is "still trying not to beat himself up too much and be too self critical," Krause says, teasing that the questions posed about temporary 118 member Jonah (Bryce Durfee) at the end of Monday's episode will only make things worse.

"Some of the things that are going to happen with the character of Jonah.... We are going to see Bobby have a difficult time with the choice that he made to make Jonah be a part of the team," Krause says. "I don't want to give away too much, but there's some things that happen with Jonah that make Bobby feel responsible. And he spirals a little bit, but he's helped out a lot by Eddie, played by Ryan Guzman, who I think has been doing a fantastic job on the show this season."

"He's been really committed," Krause continues of Guzman, whose character has been battling PTSD stemming from his tour as a medic in Afghanistan. "He's been working really hard, both on himself and himself as an actor, and I'm very proud of him."

As for what else viewers can expect from the rest of the season, "I can tell you that each individual family will be coming together and that the entire 9-1-1 large family will be coming together," says Krause, who also teases a vacation for Bobby and Athena. "Bobby feels like, 'Hey, maybe it's finally time for us to go on a honeymoon.' And he chooses to surprise Athena with an idea for a vacation — and what could possibly go wrong if they get on a cruise ship?"

On 9-1-1? Nothing... nothing at all. But we're going to grab a life preserver just in case.

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