What she knew / Gilly Macmillan (2016 fiction, F Macmillan)

Rachel Jenner is walking in a Bristol park with her eight-year-old son Ben when he asks if he can run ahead. It’s an ordinary request on an ordinary Sunday afternoon, and Rachel has no reason to worry–until Ben vanishes. Police are called, search parties go out, and Rachel, already insecure after her recent divorce, feels herself coming undone. As hours and then days pass without a sign of Ben, everyone who knew him is called into question, from Rachel’s newly married ex-husband to her mother-of-the-year sister.