On the scene with Hester and Pearl in chapter16 of The Scarlet Letter, why does sunlight shine on Pearl and not on Hester?

The allegory on Ch. 16 of the sunlight shining on Pearl is
actually a form of foreshadowing. Pearl, despite of her elfish and fiendish surreal
nature, actually will have a bright future ahead of her. She will be the heiress of all
of Chillingworth's money and she will be happily married, taken care for, and
rich.

Since Pearl is an extension of Hester, she is both
her punishment and her redemption. During these times when Pearl is little, and so close
to the time of the sin being committed, she would be problematic to Hester. However, as
Dimmesdale confessed the sin, a lifting happened where Pearl was "freed" from her
nature.

Hester, however, was not. She had made the choice
for the sin, Pearl didn't. Therefore, when the sun shone on Pearl, it was a sign that
the light will shine upon Pearl, while Hester will continue her life as the person who
wears the scarlett letter. Which, is exactly what happened.