Board Thread:Questions and Answers/@comment-29752445-20180827202712/@comment-35040906-20180827222935

that could be the case but it's likely just the wording, I believe Ymir is the spiritural ancestor of all eldians and the eldian race existed along side her.

had Ymir been the ancestor of all Eldians then Royal blood would not be special and you really can't argue incest or cousin marriages because that would still mean multiple families with enough Ymir DNA would be every where rather than being limited to the Fritz/Reiss family. and there is no question Zeke and Krista have royal blood and both have one random parent.