This book was so good. Rose and Fern are twins.
Fern has sensory processing disorder but has made a life for herself as a librarian.

Rose is very protective of her sister.... Maybe too protective. They grew up with a terrible, terrible mother or so Rose says.

Fern becomes pregnant and Rose convinces Fern to give her baby to get better Fern couldn't POSSIBLY raise a baby with her "condition" .

Rose was a terrible person. We get to see the extent of her manipulations through journal entries.

If you love Sally's past books, pick this up! It's just as good.