{alltv} Parenthood's Jason Katims on Crosby and Jasmine's Separation and Jason Ritter's Extended Stay

When Parenthood closed the book on Season 2, estranged couple Crosby (Dax Shepard) and Jasmine (Joy Bryant) were seen talking and laughing together inside his newly purchased house — the same house he bought to win her back — after months of estrangement. Their relationship seemed to be on the mend, but things aren't what they seem between the one-time lovebirds.

"When we start this season, things have not worked out between them the way people might have thought from that last image of the second season," executive producer Jason Katims tells TVGuide.com. "They're not at war, but they're not together at the beginning of the season."

Katims says the decision to keep the pair apart for at least the beginning of Season 3 stems from the desire to explore co-parenting when the parents are not together — something that has not been covered beyond the return of Amber and Drew's father, Seth, for four episodes last season.

"We're always trying to look for ways on the show to explore things that are relevant to parenthood today that we might not have explored," Katims says. "We want to explore the idea of Jasmine and Crosby living separately, trying to go on with their lives individually, but wanting to both be there for their son, Jabbar, and the challenges of that."

But just because Crosby and Jasmine aren't together, doesn't mean their love lives are coming to a complete halt. While we already know that Crosby will have a brief fling, the series is also currently casting a new love interest for Jasmine. Dr. Joseph Prestidge is described as a handsome, charming (and slightly older) pediatrician/author who asks Jasmine out after treating Jabbar for allergies. We won't say if she accepts his offer, but the character is will appear in at least four episodes this coming season.

Elsewhere on the Braverman family tree, look for Sarah's love life to heat up when her ex, Mark Cyr (Jason Ritter), returns — despite a slightly awkward reunion. "In the first episode, Sarah is going to be at the high school having a heated argument with an administrator at the high school that Jason Ritter witnesses," Katims says. "So she re-meets him in sort of an embarrassing moment. She's going through something else in the episode and winds up talking to him about it and they reconnect."

Although Sarah (Lauren Graham) has had a very busy dance card (Mike, Gordon) since she dated Mark, Katims says his return will make way for Sarah's most stable romantic endeavor yet. "We've had really interesting and great love interests for Sarah over the first two seasons, but we really wanted to do a story where we get her into a long-term relationship, or at least a longer-term relationship," Katims says. "Of course, we need to see the practical matters of how many episodes we'll be able to have Jason Ritter with us, but he will definitely have a more extended role than he had in the first season."

However, Sarah's newfound stability in her love life comes just as her relationship with her daughter, Amber (Mae Whitman) is headed for a rough patch. Now that she has graduated from high school, Amber is ready to figure things out on her own — outside of grandma and grandpa's house — even if Sarah isn't ready to let her.

"One of the things we're exploring is Amber branching out on her own and getting an apartment. Amber really wants that autonomy and independence and yet she's still young and is going to lean on her mom," Katims says. "Also, from Sarah's point of view, that's a story of being able to let go a little bit and let your daughter make some decisions on her own and make some mistakes."

Season 3 of Parenthood premieres on Tuesday, September 13 at 10/9c on NBC.