This paper uses hypothetical contractarianism to consider the value of children's rights laws as a means of protecting children. Laws protecting children from their parents have the unintended but predictable consequence of making child-rearing less desirable for some parents and thereby reducing the number of children born. Such laws therefore produce a trade-off between the expected wellbeing of actual and possible persons. I show that a possible child behind an appropriate veil of ignorance may rationally oppose laws which benefit some and harm no actual children.