Article continues below advertisementHeidi Klum celebrated her anniversary with a cheeky tribute to her man.The supermodel, 52, bared her backside in a pool with husband Tom Kaulitz, 35, for their 6th wedding anniversary on Sunday, August 3.Article continues below advertisementSource: @heidiklum/InstagramHeidi Klum and Tom Kaulitz celebrated their six-year anniversary.The couple was photographed from behind, with their arms wrapped around each other in the water. Klum donned a skimpy blue bikini, while Kaulitz went shirtless in a white baseball cap.