Helms stars as Rusty Griswold, the adult son of Clark and Ellen Griswold, who takes his own family on a road trip. Chevy Chase and Beverly D’Angelo will reprise their roles in cameos, while Skyler Gisondo and Steele Stebbins will play Rusty’s two sparring sons.
Chris Hemsworth and Charlie Day will co-star in the film, which starts production next week.
While Gillies has booked a relatively small role in “Vacation,” the up-and-coming actress boasts a large social media following, as she has 2.4 million followers on Twitter.
Gillies will soon be seen alongside Denis Leary in the upcoming FX series “Sex&Drugs&Rock&Roll,” which the network recently picked up to series. Best known for playing Jade West on Nickelodeon’s “Victorious,” she also starred alongside Keke Palmer in the horror movie “Animal” and appeared in the indie comedy “Harold.”
Gillies is represented by Paradigm.