Maggie has a secret, she has been fully potty trained for nearly six months. Bart and Lisa don't know, and Marge only suspects it. She's just not ready to give up her diapers yet. She likes the convenience, the warmth, the security, and the general feeling they provide. She uses her training potty once or twice a day to satisfy the idea that she's still learning. Otherwise she just goes in her diapers.