Nina Needs to Go

This revolves around the titular little girl needing to use the bathroom and being far away from the nearest one. She tries to get to the nearest bathroom, usually with the help of her Secret Agent-esque Nana. The fact that the path usually includes something with running water certainly doesn't help matters. Each short ends with Nina saying, "That'll never happen again, 'cause now I know, don't wait to go!". Despite this, it always happens again.