The adorable little boy turned 3 with a sweet (and creative!) bash held Sunday at Meri Cherry Art Studio in Tarzana, California, where the 12 kiddos in attendance — including Hutt’s big sister Kenzie Lynne, 4½ — could wander wherever their imagination led them.
“Hutt’s party was quite a success — a perfect excuse to play and get dirty and create,” Mitchell tells PEOPLE, sharing exclusive photos from the arts-and-crafts-inspired day that featured decor from Little Sparrow Co, flowers from Mulberry & Moss, LaCroix sparkling water and gifts personalized with Mabel’s Labels.
Explains the Hollywood Darlings star, 37, “The kids loved playing in the sensory bins. Hutton had his first experience with shaving cream and slime, and it was quite a hit.”
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For the fun-filled day, Mitchell, husband Michael Cameron and their two children were joined by a few celebrity pals’ little ones like Bill Horn and Scout Masterson‘s son Bosley Jo, 3, and daughter Simone Lynne, 6½.
“With flu season upon us, the party ended up being smaller than expected with many kids out sick,” Mitchell says. “We missed them all but it ended up being perfect.”
“The kids loved the opportunity to paint Hutton a birthday cake [and] found themselves painting not only the cake, but themselves, as well as the large window,” Mitchell recalls.
“It was pure joy for us as parents to see them enjoying being kids, getting dirty and creating art all at the same time,” adds the 7th Heaven alum.
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Aside from digging in to a cake and cupcake pull-apart creation (shaped like an artist’s palette!) from Polkatots Cupcakes, Hutton’s lucky guests got to take home quite the haul.
While the day was certainly a hit, Mitchell has one tip for other parents who are interested in planning a similar soirée for their kids.
“For all parents out there, if you plan on having an art party, you should bring an extra set of clothing!” she says, joking, “Yep, mom fail! At least I know they had fun.”