Paul says in Romans 9 that -
9:11 (For the children being not yet born, neither having done any good or evil, that the purpose of God according to election might stand, not of works, but of him that calleth
12 It was said unto her, The elder shall serve the younger.
Adam's sin caused their death. It is not necessary for Adam's sin to be imputed to a child for the child to die. The child can be prone to death despite being sinless, simply because he is a descendant of Adam.
If I say that the person who murders will go to prison, that does not mean that everyone who goes to prison must be a murderer. Saying that the soul that sins will die, does not mean that anyone who dies must have sinned.
9:11 (For the children being not yet born, neither having done any good or evil, that the purpose of God according to election might stand, not of works, but of him that calleth
12 It was said unto her, The elder shall serve the younger.
Adam's sin caused their death. It is not necessary for Adam's sin to be imputed to a child for the child to die. The child can be prone to death despite being sinless, simply because he is a descendant of Adam.
If I say that the person who murders will go to prison, that does not mean that everyone who goes to prison must be a murderer. Saying that the soul that sins will die, does not mean that anyone who dies must have sinned.
Nature also has been corrupted. The inanimate part of creation didn't sin. Why is it affected?