Who are Mitsuki's parents? From Naruto Gaiden: The Seventh Hokage, Chapter 2, Page 14.

I'm guessing one of them is Gaara. If so, who is he married to? Even when looking at the picture at the end of the chapter, I can't recall ever seeing that woman.
It has been revealed in Boruto: Naruto the Movie that, Mitsuki is Orochimaru's son.
Extract from the movie summary:

Boruto questions Mitsuki about his parentage, to which the latter says he is the son of Orochimaru. This shocks Sarada and she asks if Orochimaru is his mother or father while Boruto asks who Orochimaru is, and Mitsuki replies it doesn't matter, much to Boruto and Sarada's confusion.
source: Mitsuki