If you are sisters, that's fine. It's really because you think there are boundaries. But if they are other sisters, there will be a gap between them. After all, they are still outsiders! But there are also many situations. For example, you have grown up, have your own thoughts, have privacy, and have a separate room, so sometimes it is better to say it. You are all grown up!
Since you care more, everyone has different ideas, so I suggest you communicate with your parents and say that you have grown up and have your own space. If only you cared more!