How are Judith and Mercy different from each other in The Witch of Blackbird Pond?
Judith is a pretty girl who is smitten with a wealthy young man who is building a house for the girl he will marry (as yet an undisclosed female). She seeks his attention within the confines of the Puritan way. She likes Kit's clothes, but will not be permitted to wear such fancy things. Judith pouts when she doesn't get her own way about accepting one of Kit's dresses. She has little patience with Kit, who has never worked in a household, having had servants to do the every day chores.
Mercy had been crippled by some unknown disease when she was young. She is frail and cannot do some of the heavier chores. Mercy does not seek attention as Judith does, as she knows she will not be a suitable wife with the demands of keeping a house. Mercy is not beautiful, except for her soft, gray eyes. She does as much as she can around the house that is within her ability. Spinning is what she does best. Mercy does not want Kit's fancy clothing, but she does admire a soft, blue shawl. She will not ask for it because it is not in her nature. She is a patient girl with a kindly, gentle disposition who defends Kit's inabilities as something she will learn in time.