Request #117

 I would love help finding a book that I can’t remember much about, and I am beginning to wonder if I combined two books in my head. But I read it in the late 80s or early 90s (though it could have been published before that). It was set in the 60s, though, and I feel like it was some kind of time travel. I want to say there were twins or sisters, and I thought it was something like the Banana Split Affair but they don’t time travel. I feel like there were two guys – one who was anti-war, and the other wasn’t, and the two girls ended up on both sides of a Vietnam protest? I think it was a romance, but there was a time limit because they had to find something. This is probably not even a real book and just a combination of memories of other books, but I read it a number of times. Of course, I can’t remember it for the life of me!