Identical

I have always been fascinated by twins.  I often tease my husband that he is a terrible twin (he has a twin sister).  They don't look particularly alike, they didn't wear a ton of matching outfits, and they never had a secret twin language.  I imagine that identical twins would have done all of those things.  Maybe that's what you get when you grow up watching Mary Kate and Ashley (and yes, I know they're not identical).

But Missy and Claire are identical.  They're cousins and their parents just say it's a strong family resemblance.  But Missy and Claire have sleepovers every weekend.  They text each other constantly, and it feels like they can read each other's minds and sense their emotions.  Like they have some connection much deeper than cousins.  So when Missy gets a school project about hoaxes she decides to pass Claire off as her long lost identical twin. 

It starts as a hoax, a way to earn points in Science class but when the video is posted on the internet nobody can deny that Missy and Claire are identical.  It goes way beyond a family resemblance.  But how can that be?  The girls are cousins not twins.  Their birthdays are 8 weeks apart.  You can't fake a birthday. 

Thanks to the internet, the video spreads like wildfire.  And then something unexpected happens.  And that something changes everything.  I would love to tell you what it was but...spoilers! Caroline B. Cooney's three black swans has completely earned the label of 'thriller.'   

Uncovering a hoax...that's kids stuff. 

PS black swans: events that are hugely important, rare, and unpredictable, and explicable only after the fact.