

It must be love! While some girls snag their boyfriend's favorite button-down shirt or perfectly broken-in sweatshirt, Kristen Stewart seems to have taken possession of Robert Pattinson's prized ball cap.

Since the British actor shot to stardom in the "The Twilight Saga," the status of his hair has made major headlines. ("It's long!" "It's short!" "It's … so pointy it could be used as a weapon!") But in his downtime, when he's trying to fly under the radar and not, say, get chased down the street by groups of screaming girls, Pattinson, 25, typically hides out under a baseball cap. And not just any cap — his favorite black Baltimore Orioles hat.

[Related: Kristen Stewart: How I Said Goodbye to 'Twilight']

Pattinson has been pretty attached to the MLB team cap over the last year. One of the first times he was seen wearing it was when he was walking his dog, Bear, with his pal Tom Sturridge in Los Angeles last July. For the rest of the summer and well into the fall it was a regular accessory for the actor, whether he was hitting up Chateau Marmont in West Hollywood for a night out or doing his grocery shopping.

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The transfer of ownership from Pattinson's wardrobe over to Stewart's appeared to have occurred this year. When the twosome visited the set of "Katy Perry: Part of Me 3D" to watch the singer perform for her upcoming movie, Stewart, 22, was wearing the Orioles hat while Pattison opted for an all black cap instead. They wore the same headwear again last month when they attended the Coachella music festival. Then, during a solo trip out in New York City yesterday, Stewart was snapped sporting the Orioles hat again.

[Related: Robert Pattinson to Play Soldier Who Captured Saddam Hussein]

But this isn't the only Orioles hat Pattinson owns. He wore a second one — black with a simple script O — several times last fall. Through the years, he's also displayed his love for other teams such as the New York Yankees and San Diego Padres. And, for most of 2009, he wore a Long Beach State hat, a nod to the California school.

So one would think that because Pattison's often wearing ball hats he's a die-hard fan, right? Well, not so fast. After he had to film a baseball scene for the original "Twilight" movie, he talked about how he's terrible when it comes to athletics. "I think sports are stupid," he said. "['Twilight' director] Catherine Hardwicke was so determined to make me look like a professional baseball player she had this coach teach me this ready position, this little squat. I was like, 'I'll do it on the last day of filming.' Catherine was like, 'No, let me see it.' It was very embarrassing. I'm terrible at baseball. I'm terrible at every sport apart from running. I'm terrible at that now, too!"

Pattinson and Stewart are headed back to Vancouver in the next few weeks for "Breaking Dawn: Part 2" reshoots. Then they're expected to attend the Cannes Film Festival together later this month (she's promoting "On the Road" and he has "Cosmopolis" coming out) — and perhaps even walk the red carpet together. Hopefully they'll be wearing something a little bit more glam on the red carpet than their now signature ball caps.

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