In “The Scarlet Letter”, Pearl’s character reflects the duality of the Puritan community.
The Puritans were a group of peole who grew discontent in the Church of England and worked towards religious, moral and societal reforms. Pearl dresses in brillant clothes, which was a sign of vanity for the Puritans. Pearl is also a symbolic name, she is supposed to be rare, beautiful and white; not dressed in beautiful colors.
One of the greatest ways Pearl embodies this is that she refuses to be restrained by the Puritan way of doing things. Hester has been shunned by the society but she wants to instill proper Puritan behavior into Pearl. Pearl rejects this behavior the same way the society has rejected her and her mother. Pearl is also at one with nature, which was a "forbidden" area for most Puritans (think of the things that happen in the woods verses the things that happen in town.)
Pearl also shuns the ideas and relationships with other people in town. They consider her a devil child for doing so, even though they have done the same thing to Hester.
To me, Pearl act like what we, today, would assume a "normal" rambunctious child would act like, rather than conforming to the restraint of the Puritans.
The Puritan community's attitude toward Hester changed over time. As the "A" came to mean Angel/Able, they came to accept the goodness that was part of her nature.
This same duality is present in Hester. She accepts the punishment of the community for her violation of community standards, but it is clear that she does not feel that she has violated her own ethical standards: "What we did had a consecration of its own" (Ch. 17).
Hester has the same feelings toward Pearl who seems to contain both of these dualities. Hester says it best:
"God gave me the child!" cried she. "He gave
her, in requital of all things else, which ye had taken
from me. She is my happiness! -- she is my torture,
none the less! Pearl keeps me here in life! Pearl
punishes me...