“When all is said and done, killing my mother came easily.” For Helen Knightly, the long-suffering protagonist of Alice Sebold’s second novel, things go downhill from there. Much like Sebold’s debut, The Lovely Bones, this is a sympathetic family portrait that alchemically transmutes violence into understanding. There are also some elements that amused a different, more professional part of my brain, but I can’t say much more without providing spoilers—and for a book not scheduled to be published until October, that would be rather unsporting.