There are several characters in Daisy Miller who might win the title of “least admirable,” including Mrs. Miller, Mrs. Costello, Winterbourne, and Daisy herself. Let's look at these characters so you can decide which one should take the title.

Mrs. Miller, Daisy's mother, is a silly woman who has no idea how to act in a high-class social setting and little to no control over her children. She is scatterbrained, and she can rarely make up her mind about what is right and what is wrong, much less teach her children. Mrs. Miller is supposed to be guiding Daisy through the social mazes to make sure that her daughter behaves appropriately, but she does not even try to correct Daisy or remind her daughter of the consequences of her behavior.

Mrs. Costello is a first-class snob who is always turning her nose up at anyone who does not meet her high standards. She advises her nephew, Winterbourne, that the Millers are “common” and that he should not associate with them.

Winterbourne is a nice enough fellow for the most part, but he tends to be quite judgmental and rather stiff. Winterbourne has been raised to respect propriety at all times, and he cannot cope very well with Daisy's lack of social finesse. He does feel guilty at the end of the novel after Daisy dies and realizes, too late, that he does love her.

The we have Daisy. Daisy is a free spirit who, often inadvertently, breaks the social rules. She is a pretty girl who likes attention, and she enjoys flirting to the point of impropriety, at least according to those who set the social rules. Daisy does not take guidance well, and she makes quite a spectacle of herself with Giovanelli. Her silliness and determination to do whatever she wants catch up with her in the end, though, when she falls ill and dies.