It’s Kate’s turn to relieve herself.
For the next thirty seconds, Kate would try to expel as much urine as she could… into her big sister Lauren’s bladder. Then, Lauren had to hold in both girls’ urine for the next five minutes, allowing Kate’s bladder to rest temporarily.
After that, their roles would be reversed.
This cruel game of back-and-forth had become the only way for the girls to provide relief to their overfilled bladders. But it appears the game would soon come to an end. The combined volume of their urine in this closed system had increased substantially. The internal pressure of their bladders had made the exchange more and more difficult. Neither girl had been able to completely empty their bladders during the exchange for some time now.
Soon, both bladders would be stretched to their absolute limit, making the exchange impossible.
