Every pair of parents has a subtle competition going on most of the time. Even when they’re deeply committed to each other, daily life with a family provides no shortage of space for skirmishes. There’s a natural “gatekeeping” related to parents’ devotion to their child. Each parent believes he or she knows best on some issue of childrearing, which often results in disagreement. Mom thinks sugar should be restricted, and Dad thinks she’s being silly. Dad has no tolerance for sass, and Mom thinks