Board Thread:General Discussion/@comment-29003089-20160713040444/@comment-122.47.186.14-20160714100713

I'm not sure if it's common or uncommon for anime characters to resemble parents or not but it's up to the author to decide and not some common or uncommon rule.

But if Reki Kawahara does in fact make characters look similar to each other based on their genes, this supports the Kuroyukihime - Kirito / Asuna daughter theory.