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For more than a year, the rumor mill has been trying to make Robert Pattinson and Katy Perry happen. Now, with the actor rumored to be kaput with Kristen Stewart, speculation is once again ramping up over whether the longtime pals could be something more.

It all started on Monday afternoon, when People magazine reported that Pattinson, 27, and Perry, 28, had been spied on Saturday checking out a random wedding rehearsal at the swanky San Ysidro Ranch near Santa Barbara, Calif., not far from where Katy has a home.

"Katy and Rob were just sitting next to each other watching the wedding rehearsal in the main courtyard area," relays a guest. "They were dressed very casually. She was wearing a hoodie and big sunglasses. There was no PDA between them, and no body language that showed they were dating. They just sat together and watched."

They were apparently joined by a few friends, but their proximity at the nuptial event raised eyebrows. "They were not affiliated with the wedding party," explains the eyewitness, "and were not seen mingling with guests."

More eyebrows were raised after the story disappeared from the main People page a few hours after it was posted. It reappeared on Tuesday. Further confusing the issue: Katy's fickle former flame, John Mayer, reportedly turned up at a barbecue that she tossed at her Hollywood Hills home on Monday.

"They seem to be back together -- or back together-ish," a source tells Us Weekly. "They were very flirty and having a really good time together. They have good chemistry." Chimes in another spy, "They were definitely friendly."

Before Pattinson and Stewart's rumored breakup last week, they often hung out together with Perry, whose friendship with the British actor dates back to 2008 (they have a mutual friend in actress Shannon Woodward). Just a couple months ago, the "Twilight" twosome met up with the former Mrs. Russell Brand in Santa Barbara to celebrate the birthday of her assistant, Tamra Natisin.

Not surprisingly, Katy was dragged into the pair's latest breakup, which reportedly resulted in Rob hauling his belongings and dogs out of Kristen's Los Angeles home. According to Life & Style, Perry didn't agree with Pattinson's choice to reconcile with Stewart after her Mini Cooper-set rendezvous with married director Rupert Sanders last summer.

"Katy told Rob she didn't think their relationship could withstand the cheating scandal. And he deserved better," says an insider. "Katy liked Kristen, but ultimately she's loyal to Rob and wants what's best for him. I know he always leans on her during hard times, and Katy would do anything for him."


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