The friends group on A Million Little Things may have figured out who Barbara Morgan (Drea De Matteo) is and the complicated relationship she has to their lives at the end of Season 1, but that was just the tip of the iceberg of drama they face in Season 2. Barbara has a grown up son, PJ (Chandler Riggs), who infiltrated the group at the end of Season 1 and is now digging into their lives on his quest to answer his burning questions about who his biological father is.

The premiere saw PJ breaking into Delilah's (Stephanie Szostak) house while she was at the hospital, giving birth to Eddie's (David Giuntoli) baby. If he's already breaking and entering, what else is PJ willing to do in order to get the answers that he needs? That's an important question throughout Season 2 as PJ's quest begins to shape the next chapter for this group of friends.

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Of course, PJ isn't the only source of drama. Eddie did tell Katherine (Grace Park) that Delilah's baby is really his, putting their plans for reconciliation on hold. The rest of the friends group also figured out the baby's paternity secret, and have all gotten on board to keep quiet in order to protect Eddie and Delilah's other children. However, Katherine was overwhelmed with grief over the revelation and left Eddie, and Theo, to get her head on straight. At the end of the episode, she hadn't returned or given Eddie any hope of them getting back on track.

TV Guide spoke to A Million Little Things creator DJ Nash about Katherine's abrupt exit, Eddie and Delilah's baby drama and what PJ will really mean to this group going forward.

Katherine decides to leave. What is the ripple effect that we can expect from her making that decision?
DJ Nash
: It's interesting that you say decides to leave. I'm not quite sure that it's a conscious choice from her. I think it's almost out of desperation. She doesn't decide certain things. In your life...you may not be in the right state of mind too make these decisions. Certainly that's how our series started. I think in a similar way, Katherine's in a very desperate place. She is leaving not out of anger towards Eddie or the situation, [but] because she doesn't want her son to see her like this. Before she leaves, she makes sure that Eddie's on his way home. I think she's broken and we watched her endure a ton of stuff in the first season. Things that you wouldn't have handled as gracefully, like helping Delilah save her house, learning about the affair knowing that the whole friend group knew. There's just a point in which all of us break and she found that point.

For me, the challenge as a writer and for us as a writing team, was to both honor people who identify with Katherine. And also be true to those who are invested in Katherine and Eddie and their reconciliation. As we were looking at what would be a move that Katherine could make that would be real, be authentic and continue to tell her story, this felt like the that she'd reached her breaking point.

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Speaking of the friends group and them knowing things, what went into the decision to have them figure out that Eddie was the father of the baby and not have it be as devastating a reveal as the affair was in Season 1?
Nash: When we are thinking about this show and stories we're going to tell, I always like us to look at, 'Okay, what do we think it's going to be? And yet how can we surprise our viewers?' Goal number one is always to be authentic. The compliment the show gets that means the most to me is authenticity, but I feel like we're always looking for a way to sort of flip the card, as we say, and to surprise people.

I think we'd already played this sort of devastation and anger of learning about the affair...Going back to when I pitched the show, it was my plan to have it be that Gary had driven John to get his vasectomy. We thought that, 'Oh, that would be really cool if Gary who has got this guy code that he lives by.' It's why the affair offended him so desperately, and so deeply. The idea that he would keep a secret and hold onto it. I think it was an interesting thing to play out and another revelation into Gary and the secrets of this group. So really for us the episode was about how did we get Eddie into that delivery room? How do we make that a moving moment that we are rooting for? And hopefully we've done that...Now we're telling the story as we go into the season about a group of friends who knows the secret and who have a common goal of protecting these children.

Chandler Riggs, <em>A Million Little Things</em>Chandler Riggs, A Million Little Things

Moving on to PJ: This kid is, he's kind of shady in the premiere. He's breaking into houses already. How far is he willing to go to sort of figure out the truth about his dad?
Nash: How far would you be willing to go to figure out things you desperately need to know? I mean if your spouse is cheating on you, sometimes you do things that you wouldn't normally do because you just need to get the answer to that question. If you were feeling as though your parents, from the moment you were born have lied to you about who your father is, how far would you go to get that answer? Yes, he's making choices that go back to that sort of the mantra of our season. He's making choices that we wouldn't necessarily make, but like we do with our friends: We understand those choices and we are there for them.

He's in a very desperate place and the purpose of PJ in Season 2 is to serve as a cautionary tale. He is a young man who doesn't know who his father is. As Delilah and Eddie watch this young man make choices that are probably not correct and struggle with the fact that his fraternity was kept from him, [that] will inform their decision of what to do that with their child.

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Gary and Maggie have this really beautiful moment at the end of the premiere when he steps in the shower with her. Can you talk about the formation of that scene and why it felt so important to have that in the first episode?
Nash: It goes back to the sort of themes of our series. Life's going to be tough and challenging, but you're not alone. That's basically what happens when he steps in the shower. Without words, the two of them told that story...I think that is the message of Maggie and Gary, which is, "I don't know what comes next for you, but I'm going to be standing next to you as you find out."

That's the challenge that they face this season. Their whole relationship was based on cancer...But now that cancer's gone, what are they? There's a challenge to sort of redefine themselves. Similar to a couple where one person may drink and the other person may help them get through life. If that first person becomes sober, the role of that spouse is redefined or unnecessary. So Gary and Maggie will, I mean Gary is going to struggle to find his relevance in her life this season as she tries to figure out what her life is, the life that she didn't think she'd have, will be.

A Million Little Things continues Thursdays at 9/8c on ABC.