Is This A Normal Female/Sister Experience

Okay so I[F24] have an older sister[F26] who is only about two years older than me. We are cool for the most part until random weird disagreements happen. Anytime I talk about bettering my self or present an idea to her in any way, my sister will seem interested , but and the same time pretend to not be interested. And the next thing I know she’ll beat me to the same exact goal of mine. And then she’ll try to connect my idea to hers and act as if she’s the one including me in her original idea. And then when I act uninterested she’ll say oh I’m not trying to steal anyones dream. I’m not sure if I’m reading this correctly. I just know It irritates me when others try to race me to things. I’ll attempt to go on a diet on my own and she’ll beat me to it.