Her sister

"Lauren?" Her sister said from right outside the stall. "What's the hold up? We're all ready to go."

"D... don't come in!" Lauren cried, cupping her naked, soaking wet body.

She shivered, stomach tight with fear. She was totally naked, with nothing to wear! Her bag was gone, and with it her bikini, her towel and all her clothes! Even her Spanx and falsies!

"Lauren, what's wrong?" Her sister said with false concern.

"Nothing! Just go away!" Lauren shrieked.

"Lauren?" Now her mother's voice called out from outside the stall. "Come out of there, its' time to go!"

"I... I can't!" Lauren said, horrified.

"Can't? Why on earth not?" Her mother asked.

"I... I'm naked!" Lauren admitted reluctantly.

"Oh Lauren," Her mother sighed and shook her head. "Again?"

"It's not my fault!" Lauren pointed out defensively. "Someone stole my beach bag!"

"Sure Lauren, sure." Her mother said dismissively. "Well, one thing is for sure: you can't stay in that stall all day! Now, what are we going to do with you..."