Board Thread:Naruto Discussions/@comment-26431570-20190526171926/@comment-25632268-20190527090726

RikudoKatsudon wrote: But that doesn't explain why Tsunade, a descendant of Mito's, has no whiskers. So any guess is as good as mine.

Either another inconsistency or because she was Mito's granddaughter, so while Tsunade's mother or father should have whiskers, he or she lacked Kurama's chakra, therefore Tsunade was a child of two normal humans.

But again, Kishimoto never really cared about it.