Margaret O'Dell is one of the Fox's many neighbors. She has an initially 9-month-old daughter named Katherine, whom she overprotects, thus leading Paige to believe she is seriously nuts. Margaret O'Dell belongs to the same book club Andy is in, and that's how Paige started babysitting Katie (with a "k" Mrs. O'Dell says, but it's unknown how she can tell the difference in pronunciation between "Katherine" with a "K" and "Catherine" with a "C.").

It is not known whether Margaret O'Dell is married. One time Paige gave a bunch of kid video games to them, which were really Peter's M rated games in kid cases.

Margaret is only shown having returned home from her outing in two story arcs: one with swear words, when she finds several jars of peanut butter opened, and one when she gets angry with Paige and Katie when the latter destroys her new dress.