In a family, there are three children: X, Y, and Z. X is the brother of Y, and Y is the sister of Z. If Z is a doctor, what is X's profession if he is not a doctor?
In a family of five members A, B, C, D, and E, A is a teacher, B is a doctor, C is a lawyer, D is the mother of E, and E is a student. Who among them is the father?