Why is the subtitle of this chapter A flood of sunshine?

Notice the title of the chapter, and its repetition of the sunshine motif that we discussed earlier. The sun, of course, is an obvious symbol for redemption and life, but it was blocked earlier by a desire to hide the truth—namely, Dimmesdale's place as Pearl's father. In this chapter, however, Hester finally disposes of the scarlet letter, and Dimmesdale takes his place as Pearl's father, welcoming her with love. The sunshine breaks through the darkness of lies, shame and ignorance, and for a brief moment light shines on this newly reconciled, peaceful family.