There's a distinctive smelly mush pressing up against Leah's butt. It's still warm, meaning she messed herself recently. Leah wants to cry, but holds it in. Then she remembers the role she's playing and bursts into sobs.
"Oh, someone is a stinky butt," Tina says. She puts the pacifier back into Leah's mouth. "Don't worry, baby, I'll change you when we disembark."
True to her word, the second they get off the plane, Tina brings Leah to the restroom. By now her mess is cold and absolutely foul smelling, something Tina comments on. She also points out that the diaper is yellowed, so Leah must have gone both in her sleep. Leah was so distraught over the poop she didn't even realize.
"Why did I poop in my sleep?" Leah whispers to Tina. Tina shrugs.
"It's likely psychological. You're in a different environment than usual, just messed yourself, and are wearing something you know can be used for that purpose."
"Does that mean I actually need diapers?" Leah asks, horrified. Tina laughs.
"No. I'm sure you'll settle down once we have some time to relax at the hotel." Leah nods, relieved by the reassurance. Tina puts her into a new diaper, redresses her, and then brings her back to her father. The three catch a cab for the hotel. During the ride, Leah feels the urge to pee and, without thinking, does so. As warmth spreads through her diaper, her dread grows. Why did she do that? She could have held it for a few more minutes!