Who's interpreting the child as being aggressive?
Even if the child had been four and white and reading the Star one could expect someone to ask about the child's age and then, when the question is being returned by the child, the older person would have been
a bit baffled, not knowing what to say.
To me, who do not see colour first, it's very upsetting that every white person is being regarded as a racist however benign our behaviour.