>Should a man be allowed to marry a child?

It did happen a lot. Unless you think 12 year olds aren't children. Oh, that was in that other church.

>What about an animal he is particularly fond of? How about an inanimate object - like a life size doll? What would it matter?

Let's see, if two persons in a non-mixed marriage have an adopted child, since they can't be married, the child is legally adopted by a single parent, not by a couple.
So the kid gets to inherit only from one of them (unless there's a will, of course). But then, nothing stops anybody from leaving all their earthly posessions to a cat?

I've heard of some cases where some church (Christian, but probably not that one, rather that other one) conducted ceremonies of marrying a girl to a dead man. That's probably why nobody is making an issue of the rights of the dead people, they already have them.