“Since she has older sisters, she wanted more of a non-traditional, mature theme, and loved the idea of incorporating Coachella,” Richards, 49, tells PEOPLE of Portia, who turned 10 on March 1.
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To flush out the theme, Dash event planning decked the event with colorful tapestries, teepees, paisley-patterned pillows and desert backdrops that perfectly encompassed the relaxed and cool vibe of the Indio, California-based festival.
There was also an impressive dessert table decorated with feathers and flowers, with a collection of sweet treats like cupcakes, Rice Krispies Treats and a tie-dyed dream-catcher cake.
“I loved the cake we had made for the Kidchella theme,” Richards says. “It was beautiful and really tasted amazing!”
Of course, Portia’s friends and family were all there, including dad Mauricio Umansky and sister Sophia, 18. The gang had a blast bouncing around the trampoline park, with Umansky, 47, getting into the action and Richards even doing one of her signature splits in mid-air!
“Portia had a great time at Sky Zone. Her favorite part of the day was jumping on the trampolines,” Richards recalls.
“The girls played dodge ball and enjoyed jumping on the trampolines all day,” she adds. “I was expecting the kids to take occasional breaks but they were nonstop! She just started liking video games, which I’m not exactly thrilled about, but I’m always encouraging her to get outside and play.”
“Funny enough, my husband Mauricio was also constantly on the trampolines and I think he enjoyed it more than anyone!” Richards jokes.
Fatburger — the eatery that has been seen on RHOBH at previous parties at Richards’ house — also provided food. “We of course had to have a Fatburger truck, as it wouldn’t be a Umansky family party without one,” Richards says. “Even though Portia isn’t eating meat now, so she had their Impossible Burger!”
“The girls loved face painting with the new Snazaroo Brush Pens because they’re so easy and it doesn’t get on the kids’ clothes,” she explains. “They also loved unwrapping the L.O.L Surprise! Dolls. Each layer has something different and the girls went crazy.”
As for what Portia got for presents, Richards kept it vague.
“Portia actually didn’t ask for anything specific for her birthday this year because she likes to be surprised. She’s a typical girly girl, though, and loves clothes, shoes, makeup … I wonder where she got that from?” Richards says with a laugh.
All and all, Portia was thrilled with the party, as was Richards.
“It’s been wonderful watching her grow up and reach the double digits,” Richards says. “She’s becoming more like her sisters every day and we could not be more proud of her.”
The Real Housewives of Beverly Hills airs Tuesdays at 9 p.m. ET on Bravo.