I hope against all hope that the story told in Last Jedi is true. I really don't want her to be related to the Skywalker or Kenobi lines, I feel like that would shrink in impossible ways the galaxy far, far away.
Yeah - bit like how downright odd it is that of the two random droids on the blockade runner at the beginning of the original movie, one turned out to be from Luke's mother's (royal!) maintenance team, while the other was ...built by his father. Yanno, Darth Vader. Who happened to be from the same (Outer Rim, off-the-beaten-track) desert planet as Luke, and...
(it's not even something that started with TPM, either - by the time RotJ added the 'Leia is Luke's sister, and therefore Vader's daughter' retcon, giving another twist like the Vader = dad thing from TESB, and presumably because someone had to be that "there is another" mentioned previously, the whole shebang turns the opening of the 1977 original into ...basically a family reunion... )
I fully expect that with Abrams back on board, it'll either be his 'Leia = Luke's sister' moment for Episode IX, or he'll 'mystery box' it indefinitely (or until a subsequent film/book/whatever tries to fill in the blank). Shame if that happens, though - the idea that enough notable force-sensitive people are starting to pop up again because of a change in the Force (like the inverse of how Palpatine's machinations pulled a shroud over everything, making things harder for the Jedi to function) is neat, and having Rey (and the kid) be examples of those is more satisfying, IMO, than "...huh - turns out Qui-Gon had a granddaughter!" or what-have-you.
(likewise, if this new resurgence in force-users leads to a new Jedi order, then fine - but I get the impression that instead, we're probably looking at a new angle to handling the Force, without the monastic trappings, strict doctrines on family and the like, and thus less likely to make the same mistakes and have the same vulnerabilities as the order of old)