Let's look at all this from another angle. Sin entered the world through Adam. But Eve sinned first. Nevertheless, because she was deceived, sin is not 'credited' to her the way it is to Adam, who knew exactly what he was doing. Both were guilty of doing the same thing. But sin did not enter the world because of Eve, who sinned first, but because of Adam. Eve was deceived, sinned, and thus became a sinner. Adam was not deceived, sinned anyway, and not only became a sinner, but is held responsible for the sin nature of the entire human race. If a child is deceived by an adult, and thus does something which is sinful as a result, who is to blame?