And unlike Tess (Baker) and Annie’s (Herman) chaotic experience selling cookies with mom Beth (Susan Kelechi Watson) and new sister Déjà (Lyric Ross), Mackenzie’s has been more positive.
“When you’re really in Girl Scouts, everything to do with selling cookies at a booth is so organized!” Mackenzie, 11, tells PEOPLE. “Our cookie mom, Edurne, would never have us just showing up at a booth. You sign up for your shift way in advance and you high five the girls who are heading out while you’re setting up. We’ve got it all together.”
On the show, however, the kids get bumped from the high-traffic location they originally picked because another troupe arrived earlier, and Beth ends up snapping at the girls after forgetting the credit card swiper.
In Mackenzie’s time, though, “I’d always sell cookies at a booth with two of my really good friends. We’d do skits or sing, and it’s just so fun for everybody.”
Along with starring as 10-year-old Kate on the NBC drama, Mackenzie says that being a Girl Scout has given her a platform to influence change. She even bridged to Cadettes this year in her troop in the Greater Los Angeles area.
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“Being a Girl Scout makes me so proud,” she says. “I want to be a role model to girls and do things to make the world a better place.”
Girl Scouts also provides Mackenzie with an outlet away from Hollywood. “Sometimes people act different with me because I’m on TV — they want to know who I know or ask me lots of questions about the show,” the child star says. “But the girls in my Girl Scout troop are different. They like me for me. They’re my best friends in the world, and I know I can count on them to be there for me no matter what.”
In a new PSA, the Girl Scouts of the USA — who will have rising pop-country star and Girl Scout Tegan Marie singing on their float at the 92nd Annual Macy’s Thanksgiving Day Parade later this month — encourage girls from all walks of life to change the future.
“All girls, no matter what you look like or what your interests are, have this power in them to be and do whatever it is they want,” Mackenzie says.
This is Us airs Tuesdays at 9 p.m. ET on NBC.