I think Fred and/or George have had it.
Voldemort hates wise guys. :)
Only one of them.....
FWIW, I'm probably saying this more out of personal reasons than anything else. My grandfather's identical twin was killed in WWI -- they were in the same regiment. It affected my grandfather, obviously, but also my mom's generation and mine. It's been what -- nearly 90 years now, and it's still a very powerful influence in my generation's outlook on life. I can see JKR writing along those same lines.
Not to mention that, from a purely literary point of view, it'd be a hugely effective plot device for uncovering the "absolute evil" that Voldemort represents.
That is my fear, because they are two of my favorite characters. Although have you noticed that at least twice they have inadvertently helped the bad guys? They sold Draco the Peruvian Darkness Powder; they shut the other student in the vanishing cabinet, which led to him figuring out the secret passage from Hogwarts.