In deciding upon the thesis statement for an analysis of character, the writer may first consider the approach that he/she will take toward this analysis. That is, there are a number of interpretations of Jewett's "A White Heron"; for instance, some critics consider it a bildungsroman, others consider it much like a myth, and, as Elizabeth Ammons writes in her criticism of the short story, a fairy tale. No matter which approach to interpretation the writer takes, though, there is clearly an interplay among the characters that is central to the themes of this story.
As an example of the one approach that "A White Heron" is much like a fairy tale, Sylvia, whose name is a derivative of sylvan, meaning of the forest, seems a combination of human and fairy as she spends her days in the forest, delighting in her communion with its denizens. Having escaped the crowded industrial town of her birth, this "little maid" feels that she has not been alive until moving to pastoral home of her grandmother, Mrs. Tilley.
As the narrative progresses, the external world intrudes with the appearance of the hunter and his request that she find the white heron's nest for him. With this request, too, the grandmother gives "amazed attention," as well. It is this conflict with human desire--she "watched the young man with loving admiration" as her heart "thrilled by a dream of love"--and her spiritual awe of the
great power [that] stirred and swayed these young creatures who traversed the solemn woodlands with soft-footed silent care
that leads to Syvlia's search for the heron's hidden nest and her ultimate decision to keep the bird's secret after her transcendental experience symbolically near the "dead hemlock-tree by the green marsh." This myth-like heroine cannot give away the heron's secret. Ammons interprets the actions of Syvia as an anti-bildungsroman,
[Sylvia] chooses the world of her grandmother, a place defined as free, healthy and ‘natural’ in this story, over the world of heterosexual favor and violence represented by the hunter.
With this interpretation of the story as a fairy tale, therefore, a thesis statement regarding the analysis of characters may include the statement that the sprite-like character of Sylvia, finds identity and harmony only in the pristine world of nature as her interplay with other personages results only in detriment to her happiness.