The central characters of "Family Circus" are a family whose surname is rarely mentioned (although the cartoon of August 26, 2013, in which Billy refers to "Grandma Keane" and "Grandma Carne" indicates the same surnames as the author's family). The parents, Bil and Thelma (Thel), are modeled after the author and his wife, Thelma Carne Keane. Their four children, Billy, Dolly, Jeffy, and P.J., are fictionalized composites of the Keanes' five children. With the exception of P.J., no characters have aged appreciably during the run of the strip.