Diablo Cody Says You Should Just Go Ahead & Have Another Kid Already — EXCLUSIVE

"I honestly wish everybody had a Tully. I wish all new mothers had that kind of support in their lives." Screenwriter Diablo Cody is speaking by phone about Tully, her latest film, in which a night nurse rescues a mom of three (Charlize Theron's character Marlo) from virtually drowning in new motherhood.

Cody herself had a night nurse after the birth of her third child, though she had been originally been philosophically opposed to the idea. "At that point I had a 3-year-old son and a 5-year-old, and I was really overwhelmed and I decided to accept that help because I'm a privileged Hollywood lady who can afford it," she says in that classically blunt Cody style.

The idea of a stranger coming in to your house to watch your baby while you sleep does seem strange — Theron's Marlo worries that inviting a nanny into her house will play out like a terrible Lifetime movie where the mom is left "walking with a cane" — but Cody notes the isolation of new mothers is not how we used to do things.

The experience of new mothers, in America at least, is very different. I felt alone when I had my kids.

"When a woman had a baby she wasn't isolated, she was surrounded and nurtured by other women," she says of tribal cultures and multigenerational dwellings. "Now the experience of new mothers, in America at least, is very different. I felt alone when I had my kids."

Tully (Mackenzie Davis) is the name of the young nanny who comes to care for baby Mia, and, by extension, Marlo. She helps the baby latch, encourages Marlo to pour out her feelings, nurtures, and distracts. She is an enigma, an apparition. Throughout the film, there is a tension that comes from the belief shared among the audience that this is too good to be true. We know not to expect too much as mothers. Tully's support is so tangibly powerful that we worry it is cursed or will end too soon — therein the curse of parenthood: it's too hard/it goes by too fast!

"She'll grow a little bit during the night. So will we," Tully tells Marlo as she holds up Mia for a goodnight kiss.

For Cody, this support really was like magic. "It's like night and day what kind of parent you are when you've slept versus when you haven't," she says. The film could be viewed as a criticism of the way society isolates new mothers and leaves them to fend for themselves, she sees it as broadly "about the bond between women, and the experience of motherhood."

I did not want there to be any comfort. We needed to see [Marlo] fully underwater.

The Condition That Must Not Be Named in the film is postpartum depression. The decision not to label Marlo's malaise read to this writer as an attempt not to limit the film's relevance. But Cody says the motivation was a desire to replicate the vague, free-floating angst that defines postpartum depression. "I think there is almost something comforting about a label and a diagnosis. I did not want there to be any comfort. We needed to see [Marlo] fully underwater."

Likewise, Marlo's son, Jonah (Asher Miles Fallica) seems to have a neurological condition, but a diagnosis or label is never given. "People have asked me, 'Why didn't you say what was wrong with the little boy?' and the answer is... a lot of the time the answer isn't easy to find," Cody explains.

As Charlize Theron said in an interview with Romper, conjuring some of the uncertainty of parenthood was important. "I was hoping viewers would tap into not knowing if you're doing it all right, not knowing if you're doing the right thing, if you're messing your kids up," she said.

Importantly, Cody sees this tension as a part of every mother's journey; she is adamant that she had a very supportive partner and the cushion of privilege, felt "excited, and blissed out" about being a mother, but also recalls being "consumed by anxiety."

The lever that allows things to unravel in Tully is the arrival of Marlo's third (unplanned) child. So does Cody, who has three children, have any thoughts on being a family of five?

"Having three kids is insanity. I love it and for me three feels very balanced and they're all boys so they're their own band of hooligans. The only advice I have is just to the cherish each stage, because there is always going to be something stressful happening, you know, so you just have to savor what's delicious about it."

And if you're on the fence about leaping into the waters again? "You should do it, it's really hard but it's awesome."

Check out Romper's new video series, Bearing The Motherload, where disagreeing parents from different sides of an issue sit down with a mediator and talk about how to support (and not judge) each other’s parenting perspectives. New episodes air Mondays on Facebook.