In Model-Driven Engineering, the potential advantages of using bidirectional transformations are largely recognized. The non-deterministic nature of bidirectionality represents a key aspect: i.e, consistently propagating changes from one side to the other is typically non univocal and more than one correct solutions are admitted. In this paper, the problem of uncertainty in bidirectional transformations is discussed. In particular, we illustrate how represent a family of cohesive models, generated as output of a bidirectional transformation, by means of models with uncertainty.