Beth runs away to the wilderness following Nick's unsuccessful attempts at civilizing her through toilet training.
The Romano's and Lisa (along with Yippy constantly asking Nick to bring her things) convince Yippy to demand that Nick start changing Beth's diapers. After changing Beth's diapers, Nick is horrified over the experience, but Boomer tells him that he'd better get used to it, because changing the Beth's diaper will continue to be his responsibility until the baby is potty trained. This prompts Nick to decide that Beth should be potty trained. Boomer (and Yippy) is against this, and decides that if Nick wants Beth potty trained at such a young age, then he'll have to do it himself.
After a first try at potty training, Beth poops in her diaper, causing a frustrated Nick to take Beth to the bathroom, and refuse to let her leave until she's potty trained. Later, Nick has a lot of snacks for Beth, as they watch a scary prison movie on TV. Nick leaves the bathroom to get the Baby some cherry juice, but while he's gone, Beth escapes, by using her mini wagon to leave the house and also takes the romano's instruments along with theme (the romano's left there instruments outside). When Nick comes back to the bathroom, he finds Beth missing, and quickly fears that Beth was flushed down the toilet.
The next morning, Akari and Tohru wait impatiently to use the bathroom, while Boomer suspects that Nick is hiding something. Tohru breaks down the door, and find out that Beth is gone. The Romano's, who were sleeping in there bus nerby, then yells because there instruments are missing, and the Hiroshinos find tire tracks, as well as Beth's bottle. Nick comes to a conclusion: "Some thief broke in, flushed Baby sister Beth down the toilet, drank her juice, and stolen The Romano's instruments." Noticing his sister's handbags on the counter, Nick adds, "And he didn't even take my sister's handbags. We're obviously dealing with somebody very stupid."
Beth goes to Griller Stadium, where a large raven flies by, picks up Beth, and takes her to his nest, telling her that she will be the first meal of his mate's babies, who are still in their eggs. He tells her not to even think about escaping, because the nest is very high up in a tree, and then flies away to get his mate.
Nick and Greg follow the wagon tracks, and find the instruments. Beth starts to be scared as the baby eagles start to hatch. She sees Greg and Nick, who ask her to jump, and say that they'll catch her. Beth refuses because then Nick will make her go potty. Nick apologizes and admits that he was wrong. Then Beth says she'll think about it, but then one baby eagles gets his beak out of the egg, then Beth jumps off. Nick promises the baby that he will continue changing Beth's diapers until she's ready to be potty trained.