03/28/2008 02:45 am ET | Updated May 25, 2011

Paul McCartney And Rosanna Arquette "Spending More Time Together"

So what's going on with Rosanna Arquette and Paul McCartney?

One thing's certain, the two "are spending more time together," the actress's sibling Alexis Arquette tells PEOPLE at the TV Academy's annual Ribbon of Hope AIDS charity event in L.A. on Saturday.

Last week Arquette, 48, and McCartney, 65, made international news when a British tabloid photographed the pair taking an intimate stroll through London's Hampstead Heath.

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