In “National Lampoon’s Christmas Vacation,” the cast expands further as Clark and Ellen welcome various family members into their home for a festive celebration, complete with a few unexpected yet familiar faces. To help navigate this ensemble, here’s an overview of the Griswold family as depicted in “Christmas Vacation.”

The heart of the Chicago-based Griswold family is Clark Griswold, a man who cherishes creating lasting memories with his loved ones. Employed as a mid-level chemical engineer at NutraTox, a company specializing in food additives and preservatives, Clark has managed to secure a comfortable suburban life. His dreams include installing a pool in the backyard, and professionally, he focuses on innovations like a non-nutritive cereal varnish to maintain cereal crunchiness.

Known for his tendency to idealize family vacations, Clark meticulously plans every detail, often going to extremes—from selecting the largest Christmas tree to creating extravagant holiday displays. Despite his occasional tendency to be charmed by attractive women, his heart remains devoted to Ellen, who affectionately calls him “Sparky.”

As seen in his home movies, Clark enjoyed an all-American suburban childhood growing up in the 1950s, a childhood he looks back on with fondness and nostalgia he hopes to reproduce for his own family. The son of Clark Griswold, Sr. (John Randolph) and Nora Griswold (Diane Ladd), Clark deeply values his family time as the husband of Ellen and father to teens Rusty (Johnny Galecki) and Audrey (Juliette Lewis).

Clark has a tendency to idealize upcoming family vacations and go overboard with planning everything down to the most minute detail. He also has a tendency to overdo things from picking the largest Christmas tree to going completely overboard with his holiday decorations. Although he has a bit of a weakness for pretty ladies, when it comes right down to it, he only has eyes for Ellen, who affectionately refers to him as “Sparky.”

The daughter of Frances (Doris Roberts) and Art Smith (E.G. Marshall) and mother to Audrey and Rusty, Ellen is Clark’s beautiful bride and wife of many years. While Clark plugs away at the preservative plant, Ellen finds her fulfillment in the domestic arts, working full-time to keep her home looking like a suburban dream and remain ever-present for Clark and the kids.

Patient, loving, and devoted to her family, Ellen is the perfect yin to Clark’s yang and tends to be the adult in the room and the voice of reason when Clark goes off the rails. But it’s not always easy, and every once in a while, Ellen needs a little something for herself. When Ellen’s mother Frances catches Ellen sneaking a cigarette to let off a little steam in “National Lampoon’s Christmas Vacation,” the elder mom asks if Ellen is smoking again, suggesting that Ellen picks up smoking from time to time when things get a little intense. And in the later film “National Lampoon’s Vegas Vacation,” Ellen gets swept up in the attention lavished upon her by crooner Wayne Newton as Clark descends into the throes of a full-blown gambling addiction.

Ellen can also be incredibly kind, showing empathy to even the strangest and rudest members of the Griswold-Smith family tree. She is especially kind to her beloved cousin Catherine (Miriam Flynn), whom she seems to feel sorry for. Beverly D’Angelo would later say she sees her character in “Violent Night” as a version of Ellen Griswold, telling the New York Post, “It’s like if Clark died and she became an uber wealthy, matriarchal badass.”

As the eldest of Clark and Ellen’s two kids, Audrey Griswold has to endure recasting in each of the four “National Lampoon’s Vacation” films — a hilarious workaround for the problem of teenagers outgrowing their roles. In “Christmas Vacation,” she is played by a very young Juliette Lewis, who perfectly nails Audrey’s angsty teen vibes and constant sense of embarrassment and exasperation over her family’s antics.

Like the version of Audrey played by Dana Hill in “National Lampoon’s European Vacation,” this Audrey also has a boyfriend — albeit a different boyfriend from the previous film. While the Audrey from “European Vacation” was obsessed with her boyfriend Jack, Lewis’s Audrey expresses frustration when a boy named Alexander calls and her grandparents tell him she’s using the bathroom. And as with the other “Vacation” films, she tends to bicker with her brother Rusty. When they’re forced to sleep in the same bed together, she complains to her mother that this is “sick and twisted” while adding that she has nightmares about what he does when she’s not lying next to him.

Despite her near-constant looks of annoyance, eye-rolling, and sarcastic quips, Audrey can be truly sweet when she wants to be. After her dad’s over-the-top Christmas light display failed and Grandma Frances is trash-talking Clark, Audrey stands up for her father, telling Frances, “He worked really hard, Grandma.”

Like his sister Audrey, Griswold child Rusty gets a recast with each successive “Vacation” film. In “Christmas Vacation,” it was Johnny Galecki’s sense of humor that landed him the role — a sense of humor that would help make him famous in sitcoms like “Roseanne” and “The Big Bang Theory.”

The younger of the Griswold teens, Rusty is his dad’s little mini-me throughout the “Vacation” franchise. He clearly looks up to his father, and the pair enjoy spending time together. Rusty is a huge help to his dad, joining Clark as they pick up the Family Truckster in “Vacation” and showing eager interest in his dad’s upcoming vacation plans. Throughout “Christmas Vacation,” Russ is a huge help to his dad as the pair work together to hang up the Christmas lights.

He’s also a fairly precocious teen. In the first film, he eagerly swills down the beer his dad shares with him en route to Wally World. In “European Vacation,” Rusty easily picks up women in each country as they make their way across Europe, despite being around just 15 years old at the time. And in “Vegas Vacation,” he picks up a fake ID and gambles his way around Las Vegas, ultimately making up for his dad’s immense gambling losses with his unusual luck.

It’s well-known that Clark Griswold loves just about every little thing about the holiday season from the house full of family to the traditional holiday dinner. And he repeatedly clings to his immense optimism, even as these beloved traditions go awry. As we learn in “Christmas Vacation,” that optimism is passed down from his dad, Clark Griswold, Sr., the loving parent who helped make Clark the dad he is to Rusty and Audrey.

Clark has a strong relationship with his son, and the elder Clark Griswold seems to be an equally supportive father. When Clark turns on his light display, his father chokes up, telling Clark, “It’s a beaut, Clark. It’s a beaut,” with Clark Jr. responding that his father taught him everything he knows about exterior lighting. At the same time, he isn’t afraid to be firm with his son when it’s needed, telling Clark he is too good a parent to be losing his temper with the entire family. The elder Griswold is also not afraid to admit he got through family holidays when Clark was growing up with a lot of help from Jack Daniels.

Wife to Clark Griswold, Sr. and mother to Clark Jr., Nora Griswold doesn’t get a ton of airtime in “Christmas Vacation.” But you can tell she is an affectionate mother to Clark, referring to him as “Clarkie” at one point. Nora is also incredibly sweet and magnanimous when Clark’s light display initially flops, telling him that she can picture the whole thing in her mind and the display is “breathtaking.”

When she arrives at the same time as the other Smith-Griswold family grandparents, Nora wastes no time making herself right at home, even at the expense of a little light boundary violation. When Clark asks Rusty if he’d like to help out with the parking situation, Nora counters with a different offer, telling Russ, “Sweetheart. Your grandma’s got a real painful burr on my heel. If you rub it for me, I’ll give you a whole quarter.” Uncertain that she can get Rusty to volunteer for the gig, she also offers the job to Audrey for the same pay.

Art Smith is Ellen Griswold’s father and husband to her mother, Frances. While Ellen is sweet, patient, and loving, her dad Art is almost her polar opposite, a curmudgeonly fellow who isn’t afraid to insult his son-in-law right to his face or even to his grandchildren.

Just about every comment out of his mouth is an insult or complaint. When Clark brings the family outside to show off his holiday lights, Art demands they quickly get the show on the road, adding that he is freezing his “baguettes” off before insulting him when the light display doesn’t work out.

It’s also partly Art’s fault that Clark gets left behind when the family leaves for their shopping trip, remaining undiscovered for hours while stuck in the attic. Although Ellen is concerned as they all get loaded up in the vehicle, Art, who wants to eat so he can take his back pills, dismissively declares that Clark has his own vehicle and can follow them to their destination. But then again, without Art’s impatience, we wouldn’t have one of the most classic “Christmas Vacation” moments where we see Clark getting choked up over old holiday movies. 

Easily the most diabolical character in “National Lampoon’s Christmas Vacation,” Ellen Griswold’s mom Frances is a menace from the moment she steps foot in Casa Griswold. When she first sees her daughter, one of Frances’ first lines is an uninvited infodump about having hemmorhoids. Then again, she seems to have a knack for saying cringey things out loud as she does when she remarks that the teen Russ has turned into a big boy.

Like Art, she seems to have a very low opinion of her son-in–law, Clark. After her husband insults Clark when his Christmas display goes awry, she quickly chimes in that he’s wasted his money before commenting to her grandchildren about what a “silly waste of resources” it was. But she also knows when to acknowledge the good job her daughter’s husband has done trying to make the holiday special, remarking that the display is “beautiful” once the lights finally come on.

Husband to Aunt Bethany (Mae Questel), the toupee-wearing Uncle Lewis (William Hickey) is Clark Griswold’s uncle. It’s never made clear which of Clark’s parents Lewis is related to, the fact that he refers to Clark as “Gris” suggests he is not himself a Griswold, which would mean he’s most likely either the brother or brother-in-law to Clark’s mom, Nora or the brother-in-law of Clark’s dad, making Bethany his father’s sister.

Uncle Lewis is cantankerous and generally short on manners, bearing little patience for his senile wife. Although he’s something of a snappy dresser, always wearing a suit even in his younger years, Lewis is not financially well-off, a fact that’s stated explicitly when Ellen explains his wife’s habit of regifting items from around their home. A longtime cigar smoker, Lewis can be seen with a cigar in his mouth way back in 1955 in the home movies Clark watches while trapped in the attic. When the house fills with sewer gas from Cousin Eddie’s (Randy Quaid) RV waste disposal, his love of stogies causes an explosion, instantly reducing the Christmas tree to a burnt-out shell.

If Uncle Lewis’ tiny, senile little wife Aunt Bethany sounds familiar among the “National Lampoon’s Christmas Vacation” cast, that’s because the actor playing her once voiced some of the most iconic cartoon characters of the 20th century. One of the more adorable family members in the Griswold-Smith family tree, Aunt Bethany is played by Mae Questel, an actor who voiced iconic animated characters Betty Boop and Olive Oyl all the way back in the 1930s.

Aunt Bethany is 80 years old, something Clark brings up at the dinner table when he asks her to say grace. As demonstrated by her response to that request — saying the pledge of allegiance to the United States flag — Bethany is extremely senile to the point of near-constant confusion. She mistakes the Griswold home for the airport, and she mistakenly thinks she and Lewis are attending a housewarming celebration, wrapping their cat and a Jell-O mold to give as gifts for the occasion.

Cousin Eddie, the husband of Ellen’s beloved cousin Catherine, is the living embodiment of mayhem, a Chaotic Neutral force who occasionally veers into Chaotic Good territory due to a mix of sheer bizarre luck and good intentions. Eddie shows up with various members of his family in most of the “Vacation” films, and it’s clear that he really likes Clark despite Clark’s surprisingly patient frustration with him (given Clark’s announcement that he’d “rather see a pile of mud than Eddie” en route to Wally World).

When we first meet Eddie and his family on the family homestead in “Vacation,” we learn they have a rather large brood of children including cousins Vicki, Dale, Eddie Junior, Junior, and Daisy-Mabel. But by “Christmas Vacation,” the family has fallen on hard times, giving loads of money to a televangelist who was later involved in a sex scandal. The family has sold off most of their 10-acre estate and home, keeping only a 50-foot plot of land with an RV, some pigs, and the kids’ worm farm.

When they show up at the Griswold home for Christmas, the Johnsons have two kids in tow who aren’t previously named (Rocky and Ruby Sue). Briefly addressing the other kids’ absences, Eddie reports that the “older girl” (likely Vicki) is in rehab for alcohol addiction and their eldest son is busy moving up through the carnival business, something that seems to make his dad very proud.

As Ellen Griswold’s first cousin, Catherine is one of the sweeter family members in the Griswold-Smith family tree despite being married to one of the most obnoxious. Even Clark likes Catherine, greeting her as “Dear Catherine” when her family’s RV shows up at the home unannounced.

While everyone else in the family seems to see Eddie for the dolt he is, the romance is still very much alive in their relationship, as evidenced by the fact that they can’t stop popping out kids. As soon as they arrive at the Griswold home, Eddie asks Clark to take the kids into the house so they can spend a little private time together. In the later film “National Lampoon’s Vegas Vacation,” she and Eddie continue expanding their brood when she starts testing fertility drugs in exchange for pay, telling Ellen with a look of uncertainty, “This one’s going to be a winner!”

Cousin Ruby Sue Johnson (Ellen Hamilton Latzen), one of the younger members of the Johnson clan, lives in an RV with her parents, brother Rocky, and rottweiler Snots after losing their home. Although she calls Clark “Uncle Clark,” she is technically the Griswold parents’ first cousin once removed and second cousin to the Griswold children.

An adorable, disheveled little moppet, Ruby Sue is a sweet kid with a salty little vocabulary. She even develops a closer relationship with Clark during her family’s holiday stay, telling him during a late night conversation how much she loves living in a home where you don’t need a coat to use the bathroom. She also confesses her doubts over the existence of Santa due to the children not getting any gifts the previous year.

As one of many children of the hard-pressed Johnson parents, Ruby Sue is used to making her own fun whether it’s playing with a worm farm, a snake pit, or any number of other dangers out on the family plot. We learn from her Great Aunt Frances that Ruby Sue was once cross-eyed, but it wasn’t congenital; rather, she’d acquired the condition after falling into a well and it later self-corrected when she was kicked by a mule.

The second of the Johnson siblings to tag along on the family’s holiday vacation at Casa Griswold, Rocky Johnson is the darker-haired brother of Ruby Sue. Although he isn’t explicitly named in “National Lampoon’s Vacation,” it’s implied that, like Ruby Sue, he was present among the other Johnson kids. Like Ruby Sue, he is Clark and Ellen Griswold’s first cousin once removed as well as a second cousin to Rusty and Audrey.

Unlike chatty Ruby Sue, he doesn’t have much to say in “Christmas Vacation.” But he does occasionally act out when he’s feeling emotional, something his sister Ruby Sue seems fairly empathetic about when he bites her thumb while they’re trying to sleep. Rather than complain about Rocky, Ruby Sue takes the time to explain to Clark that her brother is actually just nervous because he doesn’t believe Santa will come this year. Ellen also later revealed that Rocky said as much to her in an off-screen conversation, inspiring the Griswold parents to pitch in on gifts for the family. Rocky also has an unidentified lip fungus, according to Eddie.