The family vacation provides an ideal opportunity to test those relationships. For writers, the vacation plot is a petri dish filled with parents and children, long-standing and unresolved angst, and a confined space. For readers, we’re transported to a dreamy destination, either one we’re familiar with or wish we were. In Ryan Effgen’s Make Nice, we join the Pickford family for a week-long stay on a fictional version of Mackinac Island in the u…