Board Thread:Boruto Discussions/@comment-25319479-20181020083112/@comment-35480222-20181020215829

I don't think he is his son because we know he comes from Konoha and not from an outside village. The most solid theory so far is "Samahadi against the monkey" from Japanese myth, this somehow involves Sarutobi clan (that means monkey). This makes him someone that hates the Sarutobi clan and around the age of one of these gruops:(Itachi, Yamato, Kabuto) (Asuma, Kakashi, Guy, Anko) (Minato, Shikaku, Kushina, Nagato).