Drew Barrymore was honored at the annual Children’s Hospital of Los Angeles Once Upon A Time Gala in Los Angeles on Saturday night, and ET’s Lauren Zima caught up with her on the red carpet, where she opened up about her love of Halloween and the challenges of co-parenting.

So how does Barrymore make it work as a newly single mom-of-two? “Plans,” she explains. “Constant plans. We, as a family, have three dates for this Halloween.”

Between all the planning and coordinating with her ex-husband Will Kopelman’s family — the couple’s divorce was finalized in August after four years of marriage — Barrymore says she feels honored for the continued love and acceptance from her children’s paternal grandmother. “[It] means the world to me,” she says.

Still, the 41-year-old actress and producer is looking forward to the hectic Halloween in front of her. “It’s like the best day ever,” she gushes. “It’s the only day that’s acceptable and not totally creepy to wear a mask, so God bless Halloween! I love it. I get to be an anonymous parent that night, so I’m into that!”

Speaking of dressing up, Barrymore looked stunning in a black, off-the-shoulder Elizabeth Kennedy New York dress, with her hair swept back in a loose braid.

But with the busy demands of motherhood and entrepreneurship — Barrymore has her own makeup line, Flower Beauty, as well as her own production company, Flower Films — the star says she saves getting made up for special occasions these days.

“I have a motto, ‘A smile is better than any lipstick you’re ever going to buy,'” she says. “So if I can be just me every day of my life and have the makeup moment feel special or like I’m carving something out of my time, or I’m making an effort to show someone in a meeting or a dinner that I’ve made the effort — it feels special. But every day is not like that.”

That explains some of the stellar makeup-free looks the How To Be Single producer has been posting to her Instagram lately!

Barrymore was honored at the Children’s Hospital gala with the Courage to Care award, given to those who champion children’s welfare-related causes. She posted a photo of her award to Instagram on Sunday, writing that the honor “will just make me work harder to earn it!”

But that wasn’t all! Barrymore also got to fangirl over fellow Children’s Hospital volunteer, Katy Perry, who performed at the gala.

“Oh yeah! And this happened!!!,” she wrote on Instagram. “@katyperry my fellow @childrensla representative tonight at the gala!!! #loveher #roar me and my daughters listen to her with such joy!”

Plus, the actress had a very special date for the gala: 13-year-old Madison Elizondo. Barrymore met Elizondo, who has been treated frequently at the hospital, last year, and the two formed a friendship. ET can exclusively reveal that Barrymore gave her pal the full red-carpet treatment Saturday night! Elizondo was styled by Barrymore’s personal stylist, and the actress’ team also did her nails and makeup.