If B is a sister of A and C is a brother of A, what is C to B?

In this scenario, we have a family relationship where B is identified as the sister of A. This means B and A share the same parents. Additionally, C is described as a brother of A, indicating that C also shares the same parents as A.

Since B is the sister of A and C is the brother of A, B and C are siblings in relation to each other. Therefore, C is B's brother. This conclusion follows directly from the definitions of sibling relationships; all three individuals (A, B, and C) are siblings, and the relationship structure confirms that C must be classified as B's brother.

Understanding family relationships in this way is crucial, as it relies on the definitions of sister and brother being equal to sibling in a familial context.