Secrets - Different and yet the same

Here are three books published in 2016 that have different settings, (although the plots are slightly similar).  However, each main character has a secret.  And all those secrets are the same.  In a later post, I will tell you what the secret is.  Let's see if any of my readers already know.

The Kidnap Plot by Dave Butler.  When Charlie's inventor father is kidnapped by the Anti-Human League, it is up to Charlie and a ragtag band of characters, including a troll and two aviator/thieves to save the day.  This is a stem-punk romp.

The Adventures of Lettie Peppercorn by Sam Gayton and Poly Bernatrene (illustrations).  Before her mother disappeared, she told Lettie to never go outside.  Then a stranger offers to sell Lettie his wonderful new invention - snow.   The stranger also knows where Lettie's mother has gone.
So, armed with this marvelous snow, Lettie heads off to put her family back together.

Rebel Genius by Michael Dante DiMartino  Giacomo is a street urchin with a need to draw, and draw and draw.  But in his country - a land similar to Italy in the Renaissance - art is forbidden.  The Geniuses that aid artists - birds with rare powers - are hunted down and caged.  When Giacomo is attacked by two Lost Souls, a strange explosion of light and energy results in the arrival of a Genius of Giacomo's own - and his induction into a secret group of talented children.  Their benefactor has dangerous plans.  Soon, the children are put in life threatening peril.