A child (of any age) from your spouse's former marriage who treats you like shit because they can.

Also one who manipulates their divorced father via his guilt. This manipulation can be to get him to buy them things, or to get daddy yelling on step -mom
The stepbrat is relentless in his victim hood, telling lies to make dad's wife look bad.

The stepbrat spewed her foul psychotic one-liners at me while her father just stood there, watching.
by OverIt December 4, 2013
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