 Another limitation of Lewis’s original presentation is that it does not allow imposing constraints on the choice of counterparts for different individuals. Suppose we hold that Elizabeth II is essentially the daughter of George VI, and suppose there are worlds at which both Elizabeth and George have multiple counterparts, perhaps in different epochs of eternally recurring time. Some Elizabeth counterpart will then not be the daughter of some George counterpart. By Lewis’s 1968 account, ‘Elizabeth might not have been George’s daughter’ then comes out true, contrary to our supposition. This problem was raised in Hazen (1979). Hazen suggests a revised analysis in terms of sets of counterpart functions. Lewis (1983d, 44–5) instead suggests that we should understand ‘Elizabeth might not have been George’s daughter’ as a de re claim about the pair (or fusion) of Elizabeth and George. Hazen (2012) argues that neither proposal fully avoids the problem.