What is the importance of the HP in the novel, The Good Daughter?

The HP is a symbol of stasis. When Charlie and Sam return to the house where their mother was murdered, the HP has changed little in those 28 years. The girls notice that many of the boxes that Gamma got from the thrift store have never been unpacked. The house and its lack of changes also parallel with Charlie's inability to move forward with her life. Symbolically, she packed the emotional devastation associated with her rape up in a box. Just like the unpacked boxes in the HP, she has never dealt with it.