I love it when people make these stupid arguments to try to rally around people like Roy Moore.

1) In the story, Mary and Joseph are married.   Although that should also be a problem for bible believers considering it would be a child bride but whatever.
2) Mary was a virgin.
3) Mary did not get pregnant by Joseph.

Here is a tip.  Don't try to use the bible to defend someone who targets children sexually.  It won't work well for you at all considering all the examples of what we would consider child abuse.