'Parenthood's' Jason Katims, Monica Potter on Kristina's Life-Altering News and the Journey Ahead

Monica Potter Parenthood Still - P 2012

Monica Potter Parenthood Still - P 2012

[Warning: This story contains spoilers from the second episode of Parenthood's fourth season.]

NBC's Parenthood delivered an emotional blow unlike any other in the series' three seasons Tuesday.

While still adjusting to Haddie (Sarah Ramos) going off to college, Adam (Peter Krause) and Kristina (Monica Potter) were confronted with their own mortality during "Left Field," the second episode ofits brand-new fourth season Tuesday.

Breast cancer. 

"My wife went through it a couple years ago and it's a story that I've been, in the back of my mind, wanting to tell," showrunner Jason Katims tells The Hollywood Reporter, noting he felt the same trepidation when mulling whether or not to include another personal story, Max's Asperger's, into the NBC family drama. "We ultimately decided this was a story we could tell in a unique way and that it would be something that would be a very emotional and poignant story with many positive moments, too."

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While the EP was discussing the then-potential story line with his producing partners, he received a call from Potter, who had just gone in for her first-ever mammogram and wound up contacting Katims to suggest the show explore a breast cancer story line for Kristina.

"I had to go for a mammogram -- my first mammogram ever -- and It was really scary and I didn’t know what to expect," Potter tells THR. "I reached out to Jason and said, 'I got a little scare. I think I'm fine but what if we talked about Kristina having breast cancer?' I e-mailed him and within the hour, he e-mailed me back and said, 'I have the chills as we just broke that story for Kristina for this season.'"

"It was crazy because his wife, Kathy, actually went through breast cancer and they have a knowledge of the disease and all these resources," she adds. "It's a very common thing nowadays; a lot of women have it and a lot of women are going through it and coming out OK but I thought it was interesting and really timely to kind of have that story."

The story line, which will extend through all of Parenthood's fourth season, will impact all of the Braverman family, with members of the large (and close) family responding to her diagnosis in different ways. Haddie, for one, will come back and forth between home and college as she ponders how she can be 3,000 miles away as her mother and best friend is confronted with her own mortality.

"Suddenly you're confronted with your mortality or the immortality of a loved one and you have to face that," Katims says. "We were really adamant about telling the story in a very real way, including the joyful, silly moments and the times when you're not giving in to your emotions about it. We are exploring the story in a way that is very human and real, taking it very seriously but at the same time, Kristina really needs to be brave for her children. This isn't just going to be them sitting around feeling sorry for themselves."

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While Haddie will continue to shuttle back and forth, Max (Max Burkholder) will handle the news in his own way while others will struggle how to react to Kristina's news.

"Max doesn't fully get it 100 percent; he gets it in his Max way," Potter says. "The Bravermans rally behind her; they're with her 100 percent and a lot of them don't know how to react. They’re all learning about the disease as they go, and learning what the battles are, what it’s like, different types of treatment and they will definitely be a guiding force behind her."

Her own family, meanwhile, has yet to be explored, with Potter pushing hard to see the breast cancer story line push into Kristina's pre-Braverman relationship with her biological family.

"They never showed up when she had the baby; I'm really, really hoping that we see them this year," she says, eyeing her friend Jack McGee (who played Mark Wahlberg's father in The Fighter) and either Goldie Hawn or Carol Burnett for the potential roles. (For his part, Katims says it's a story the writers have definitely talked about, but "not something that we have yet figured out how to incorporate into the story.")

As for how Kristina will change, Potter says that her character's old habits will fall by wayside as she begins to deal with the life-altering news she shared with Adam at the end of Tuesday's episode.

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"Last season, I remember Kristina coming across as very sometimes controlling and bossy but always with the best interest of others and this year you’re going to see her a little bit less in control," says Potter, who notes the scene in which she tells Adam the news was filmed at a market near her home. "When we were shooting it there, it was really weird and gut-wrenching because I felt like I was actually telling my husband."

Ultimately, Potter hopes the story line creates a dialogue and encourages women to go in regularly for mammograms. "I hope we can push other women to go because it affects everybody in your family."

"I just got episode six and holy moly, it's a punch in the gut," she notes.

Parenthood airs Tuesdays at 10 p.m. on NBC. Hit the comments with your thoughts on Kristina's emotional story line.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit