Ms. Sinclair is the head of the Ayn Rand School for Tots. Her brother is Llewellyn Sinclair. She has modeled the workings of the school after the philosophies of Ayn Rand and tries "to develop the bottle within." Posters referring to Rand's ideas are hung throughout the nursery, including "A is A" and "Helping is Futile." She is also opposed to pacifiers, causing Maggie to rebel and retrieve her pacifier in a manner similar to the escape of the POWs in The Great Escape. In one scene she is found reading a book called The Fountainhead Diet.