How 'Guardians of the Galaxy Vol. 2' reflects its director's painful childhood

If there is a single biggest difference between Marvel's rock-star "Guardians of the Galaxy" franchise filmmaker James Gunn and the DC universe's visual stylist Zack Snyder, perhaps it is this: Gunn knows how to put the "fun" in family dysfunction.

The writer-director of the new "Guardians of the Galaxy Vol. 2," unlike a few of his superhero-movie peers, has a precise ear for the kind of intimate carping that rings as genuine - the loving invective of the tongues that bind.

This gift, which helps makes the Guardians so appealing, has its roots in Gunn's own sometimes difficult '70s and '80s childhood in the St. Louis suburb of Manchester, Missouri. Long before he considered Hollywood as a career path, his Irish Catholic family was providing lessons in dramatic tension.

"I grew up in a dysfunctional family, and I'm not betraying anything by saying: My dad has been sober for a long time, but he was not sober when I was young," Gunn tells The Washington Post's Comic Riffs. "And that created a lot of turmoil in the family. I came from many, many alcoholics in my family."

Sean Gunn, the director's younger brother, says that he experienced that turmoil, too, though "to be fair, it was easier for me than it was for my [older siblings], because I was the youngest of six. It got better as we got older."

Sean Gunn, who has appeared in many of his elder brother's screen projects - he's the comic-relief assistant named Kraglin in "Guardians of the Galaxy 2," as well as a motion-reference actor for Rocket Raccoon - says that having a difficult father did have a positive effect: "It contributed to the really tight bond that many siblings share with each other."

And James Gunn notes the conflict of his young home life was leavened by the love. "Being very Irish Catholic, I knew my parents loved me, and that was the most important thing." The forgiving filmmaker even cast Jim Gunn Sr. in a bit role in the "Guardians" sequel, albeit with the credit as "Weird Old Man."

That sort of love-conquers-conflict dynamic, the filmmaker says, "is what 'Guardians of the Galaxy 2' is all about," as Peter Quill (Chris Pratt), the space hero with serious daddy issues, squabbles and fights alongside his "adopted" family that includes a green-tinted love interest (Zoe Saldana's Gamora), a trash-talking critter (Bradley Cooper's Rocket Raccoon), a taunting blue hulk (Dave Bautista's Drax) and an adorable sapling (Vin Diesel's Baby Groot).

The overarching theme of the movie, Sean Gunn says, is that this odd band of space protectors is trying to evolve from a dysfunctional family to a strangely functional one.

When you're part of a big family, the younger Gunn says, "there are certain skills you need [to survive] and that you learn."

And now, says Michael Rooker, who has worked with James Gunn often - he plays the space pirate Yondu in the "Guardians" franchise - the director has become like a paternal authority figure himself.

"Off set, he's like my bastard brother," Rooker says with a hearty laugh. "But on set, he's my dad."