Great colour and expression. The direct, front light (on camera flash ?) seems a bit harsh and doesn't give a lot of shape to the features. background doesn't really distract but doesn't really enhance the shot either - some sort of contrasting or complementary colour with the pink would really be great.
These are the cutest trick or treaters. :) "Who are you and what am I doing here?" :D A cute portrait, but had the background been more out of focus or darker, and the subject less centred, the impact would have been higher.