Rihanna and her “friend” Matt Kemp must be getting pretty serious! Word on the sidewalk is that RiRi flew all the way to Arizona from Berlin to be with Matt and his family at Matt’s “Ante Up for Autism” charity bash last weekend. This event meant a lot to Matt and the Kemps because Matt’s brother is autistic.

She had performed at the Echo Awards in Berlin on Thursday but then hopped on a plane shortly after. “Matt was happy she came,” says an inside source on Rihanna making it to the event.  “It was an awesome show of support.” Besides the other pro baseballers in the house Saturday evening, Kemp’s family also attended, and they met Rihanna for the first time. “Rihanna fit right in as if they all knew each other. It was comfortable.” The fundraising gala kicked off with Vegas-style gaming and cocktails, a live and a silent auction, followed by dinner and dancing. The second-annual event raised $170,000 with only 150 people in attendance.

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Up next for Rihanna is the Kids’ Choice Awards in Los Angeles at the end of this month (Sat. Mar 27), where she is set to perform but won’t be taking home any awards because she didn’t score any nominations.