have a word with them about your brother im sure they will have their reasons, its sad to say girls tend to get treated different than boys, there were twins in my year for instance one boy one girl, obv the same age, the boy could stay out all night do what he wanted and the girl had to be home at 10/11, its sad but girls are seen as more vulnerable. I dont know if you can change their views, but its probably worth more talking to them and saying you feel its unfair after your brother got treated differently. My mum was strict like your parents but let me stay in my room with my bf when i was 16 (nearly 17) but simply because she liked him and trusted him, perhaps this is an issue your parents may have?