Is Kotori Shido's sister?

Excuse me, could you clarify something for me? The statement 'Is Kotori Shido's sister?' seems to be a bit incomplete or possibly phrased in a way that could lead to confusion. Are you asking if Kotori Shido has a sister, or if someone else is being referred to as Kotori Shido's sister? Could you please provide more context or rephrase the question to make it clearer? I'd be happy to help with any information I can, but I need a bit more guidance to give you an accurate answer.