Despite her parents' divorce, her father's coming out as gay, and his plans to marry his boyfriend, ten-year-old Bea is reassured by her parents' unconditional love, excited about getting a stepsister, and haunted by something she did last summer at her father's lake house.

"When Bea's dad and his wonderful partner, Jesse, decide to marry, it looks as if Bea's biggest wish is coming true: she's finally (finally!) going to have a sister. They're both ten. They're both in fifth grade. Though they've never met, Bea knows that she and Sonia will be perfect sisters. Just like sisters anywhere, Bea thinks. But as the wedding day approaches, Bea makes discoveries that lead her to a possibly disastrous choice."--