Sarah was the first name of Letitia Ketterley's housemaid. Her last name is not known.
On the day that Jadis arrived on Earth, in England, Sarah was, for some unknown reason, having a "a wonderful day," a "beautifully exciting morning," and in fact, "had never had such a day before." She seemed to be completely un-bothered by the activity surrounding her, although whether this was due to a lack of understanding by her over what was happening, or some joyous event in her life not mentioned in the chronicle, is unknown.
It is possible that she was simply unused to there being so much activity and excitement going on, on the day that Jadis caused so much havok. Jadis's arrival certainly was exciting and Sarah would most likely had never had a day like that before (or since). Housemaids, during Sarah's day, led very dull lives, with exceedingly strict rules. They usually had only one day off every two weeks, if even that, poor wages, as well as weren't allowed much of a social life. Needless to say, it would have been a very boring life and Jadis's arrival would be the most excitement one would have ever had.
After Jadis had met and assaulted Letitia Ketterley, by throwing her clear across her room, Letitia sent Sarah to the police station, to report her.
It was generally Sarah's job to deliver Mabel Kirke's meals.
Nothing else is known about her.