The writing is beautifully crafted, as can be seen from the numerous quotes. I could not find that Ms. Sebold had any experience with the afterlife, but she did base the novel on her own brutal rape when she was in college. That rape affected her and all of her writing ever since.
“The dead are never exactly seen by the living, but many people seem acutely aware of something changed around them. They speak of a chill in the air. The mates of the deceased wake from dreams and see a figure standing at the end of their bed, or in a doorway, or boarding, phantomlike, a city bus.” ― Alice Sebold, The Lovely Bone
“There was one thing my murderer didn't understand; he didn't understand how much a father could love his child.” ― Alice Sebold, The Lovely Bones
This is also passed on to Susie's sister and little brother.