Family Attribution Modernization Act This bill modifies family attribution rules for purposes of tax-exempt pension and profit sharing plans (e.g., 401k retirement plans) to provide that (1) community property laws shall be disregarded for purposes of determining ownership under attribution rules, and (2) attribution is eliminated for spouses and minor children under certain circumstances. The family attribution rule treats an individual taxpayer as owning property interests (e.g., stock) that are owned, directly or indirectly, by the individual's spouse, children, grandchildren, and parents.