She doesn't believe him

"You realise I'm your sister right?" She asks in in surprise. "Just do it back up."

Ben fumbles with the bikini strap for a moment, "um.....I think it's broken." He finally replies.

"What?" Emily turns her head and then reaches behind her back feeling for the strap clasp. "Seriously, what have you done?"

Very carefully she wraps her towel around her, before pulling off the bikini top and looking at the clasp. "Great, it really is broken. It's a good thing I have a spare."

Slowly she sits up, scowling at her brother, before climbing to her feet. "I'm going back to the room to change. Keep the sunbed safe will you?"