Pippa Middleton has been on her best behavior since getting into a spot of trouble back in April.

On Thursday, Kate Middleton's younger sister, 28, looked demure in a white blouse and a navy skirt as she watched Serena Williams take on Hungary's Melinda Czink at Wimbledon (and shared a laugh with her younger brother James).

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The former scene-stealing bridesmaid has been staying out of the spotlight since April, when she was photographed with pals in Paris -- one of whom thought it'd be funny to point a gun at the photographers who were following them. (An eyewitness reported them to police, though Pippa was eventually let off the hook.)

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Still, she's been "advised by her parents to stay out of the spotlight for a bit," a Middleton family pal tells Us Weekly. "She's being careful, thinking twice before she acts or speaks!"

This article originally appeared on Usmagazine.com: Pippa Middleton Comes Out of Hiding at Wimbledon