Paris and Nicky Hilton have pounded the pavement for good cause. On Sunday morning, the hotel heiress ran at the Tokidoki Youth Relief Run on Santa Monica Beach as they joined Fergie, Josh Duhamel and Dianna Agron in his effort to raise money for the relief effort in Japan after it was struck with a devastating earthquake and tsunami.

Before taking part at the event, 30-year-old Paris also took to Twitter to share that she was joined by sister Nicky Hilton for the run. After the two mile run along the beach, she tweeted, "Felt so amazing to support Japan today and run in the @JoshDuhamel @Tokidoki #ReliefRun with @NickyHilton @BrookeBrinson and @TheFergie."

Nicky Hilton knows exactly what to do when the weather outside is frightful – pack your bikinis, fly to Hawaii and splash around in the Pacific Ocean! The other Hilton sister spent the day on the beaches in Maui with boyfriend David Katzenberg and in true Hilton sister fashion never removed her over-sized sunglasses.

Sunbathing Nicky Hilton keeps her bikini body under wraps with a towel at the pool in Miami. With her hair tied up in a simple bun, a clutch of silver bracelets on her arm, an a pair of designer sunglasses, she was perfectly prepared for the sunny weather.