Julianne Hough was in a bikini yesterday to go for a swim at her Miami hotel! She cooled off in the water after a stroll on the sand with her mom, Marianne, and her shirtless Rock of Ages costar Diego Boneta. Diego was still by her side to splash with other friends, as he and Julianne enjoyed the afternoon off from movie making. Diego's no stranger to seeing her in a two piece, after he had some Julianne Hough bikini time on set in late May. Julianne's real-life leading man is Ryan Seacrest, and he was in Miami just over a week ago to see her. Ryan couldn't be there this weekend, because he was off at producer Ryan Kavanaugh's Capri wedding. Last night, though, was all about family for Julianne, since she shared a photo of her and Marianne making dinner together.