They vs. He/she

The sentence beside 1. has an error in pronoun/antecedent agreement. The words your child are singular. The pronoun they, which refers to your child, is plural. These words should both be plural or both be singular. Because a parent might have only one child, meaning he/she doesn't have children, the correct way to word this sentence is as follows:

1.  Let your child choose what he/she wants to read... .

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