Kristen treats her man to a piano to mark their three-year anniversary.

Kristen Stewart has reportedly bought Robert Pattinson a £50,000 piano as a surprise.

OK! magazine report the 21-year-old actress, who plays Robert's on-screen wife in Twilight, marked the couple's three-year anniversary by going all out on a high-end piano .

A source revealed: "Kristen wanted to get a huge surprise for Rob for their anniversary later this month."

"Robert's been playing the piano his whole life and admits it's the perfect escape for him when the showbiz world, paparazzi and fans get too much. Playing the piano is Rob's therapy when he needs to be alone, to think, to get emotional and creative.

''He's really musical and loves to sing as well.

''Kristen has been searching around specialised, high-end piano shops in Los Angeles. She's been talking to top musicians about the best piano for months. Robert has always wanted a Steinway grand, so that's what she opted for.

''She blew £50,000, knowing that he'd love it.''

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