Board Thread:Boruto Discussions/@comment-33156423-20170930194448/@comment-26580493-20171002170502

I'm pretty sure they are two separate people of the same familial line. If he is related to Yagura (which I believe to be true given the present evidence), it is possible the "scar" could be hereditary. In the same sense that Naruto has whiskers akin to the Ninetails, Yagura's scar matched the Three tails. So it stands to reason that if Naruto's kids could have a genetic trait like that Kagura could as well.