If you've ever wondered why there are so many celebrity couples walking around who look like siblings, there's a sociological explanation for that. Apparently, humans are more likely to be attracted to things that look similar to them. And, if you happen to be of the more attractive variety, hooking up with someone who looks like you means you won't tarnish your precious "gene pool."
I guess that sort of makes sense, but that still doesn't make these brother-and-sister-looking couples any less creepy:
1. Benedict Cumberbatch and Sophie Hunter
Sophie was fortunately spared the more "reptilian" aspects of Benedict's face, but the similarities are definitely there. But hey, since they're both British, there's a likelihood that they're at least third cousins.