A group of children and their slightly inattentive parents are the time-honored ingredients for narrative mischief. In KL Pereira's "The Children's House," the mischief involves the slipping and sliding boundaries between one space and another, one family and another, one person and another. Pereira evokes an eerily calm world in which families and identities can be pilfered and misplaced as easily as an object from a mantlepiece.