This is a really interesting historical, young adult novel about a young teen living in thirteenth century England. This fictional diary of Catherine (or "Birdy") reveals much about the role of women in medieval Europe.
The first part of the book is all about Catherine's life at home. She had a very loud (and fairly obnoxious) father and a really compassionate and sweet mother. They live on a feudal manor in the year 1290. Here she talks a lot about her daily living such as spinning wool into usable thread, killing fleas in order to keep both animals and humans healthy, attending rare festivals (such as May Day and Easter), and embroidering many pieces of fabric.
One event of note happens after Catherine's uncle ("Uncle George") comes home after fighting in the Crusades. He falls in love with Lady Aelis, and she falls in love with him. They are unable to marry because Lady Aelis is far above George in society (and feudal society doesn't allow such a marriage). Instead, the two end up marrying other people who don't provide a good personal fit, only a good "societal" fit.
The main part of the plot has to do with Catherine herself resisting marriage to a man she doesn't love. Catherine's mind runs wild. Catherine's father could force her to marry the young man. Catherine could run away. Catherine could become a monk (or, at least, she thinks she can). Catherine could travel overseas. Catherine herself could fight in the Crusades.
As you can see, Catherine's imagination provides a wealth of impossible possibilities. Eventually Catherine tries to counter the proposal with a visit to her Aunt Ethelfritha who has married Uncle George. Unfortunately, Catherine's aunt is unable to help because she has gone completely insane due to her own botched marriage.
In conclusion, it's important to note that Catherine's story does end happily. When she arrives home from her aunt's house, Catherine learns that her betrothed has been killed and, therefore, she will be betrothed to his son: Stephen. Stephen is clean-cut, young, and smart. Catherine is happy with this match and awaits the marriage with joy.