Gypsies by Robert Charles Wilson
Karen found out when young that her brother and sister had the power to access parallel worlds. Presumably she had the power as well, but she repressed it – cowed by a tyrannical father who made them move “like gypsies” every few years to escape detection. Even so, a mysterious Grey Man managed to follow them, and now our middle-aged heroine fears he’s coming for her 15 year-old son who also has “the power.”
In the wake of an awful divorce, she takes her son and flees Canada to find her sister living in a nicer “parallel” version of California. She hopes her sister can help her unravel their real parentage and origins since their anger-prone brother disappeared years ago. Haunting with fascinating details of the differences and similarities of the parallel worlds.
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