TASK DEFINITION: You are given a target person and two sentences. Your task is to determine whether the second sentence conveys either a stereotype, anti-stereotype, or is unrelated with respect to the first sentence and the target.  A stereotype is a widely held but oversimplified notion of a group of people. An anti-stereotype is an idea that goes against the widely held but oversimplified notion of a group of people. Sentences and targets are unrelated if there is no relevance between them.
PROBLEM: Target: sister 
The sister was instigating fights with her brother. She loved to pick fights and get him into trouble.

SOLUTION: stereotype

PROBLEM: Target: schoolgirl 
Look at that schoolgirl over there. The fog is thick.

SOLUTION: unrelated

PROBLEM: Target: himself 
I wanted for him to introduce himself. He does bend over backwards to make sure I am happy.

SOLUTION:
anti-stereotype