The US actress was pictured on the red carpet in Los Angeles yesterday (17 December) and she looked barely recognisable.
Abigail, now 17, was rocking a form-fitting metallic gown with long sleeves, which she teamed with a pair of grey suede heels.
She was carrying a coordinating clutch bag and had her hair swept into a low ponytail, which had been tonged into tight curls.
Abigail was just 10 when she shot to fame as lead character Olive Hoover in the 2006 comedy-drama movie Little Miss Sunshine.
Playing the part of a cute beauty pageant hopeful with a nutty family, Abigail went on to be nominated for several prestigious acting awards.
Writing at the time, one critic said: "If Olive had been played by any other little girl, she would not have affected us as mightily as it did."
Abigail went on to star in 2009 movie My Sister's Keeper and, more recently, acted alongside Halle Berry in thriller movie The Call.
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