Happened with my brother, but honestly siblings do love each other and in all fairness you could just annoy her back. She is probably annoying you because she likes the reaction you make.
we're in the same grade, and have to share a bedroom (our place is tiny, and it was better to share with her than the baby!).
we fought like crazy for the first 3-4 months we lived together, but eventually had to just talk it out and make friends. Can't share a room with someone who drives you nuts.
The baby (ok, he's 2) really drives me crazy sometimes, so I just hide in my room with a book. Or I go for a run with my stepsister.
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14 male and BI
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