In a family of six members A, B, C, D, E, and F, A is the father of B. C is the mother of B and D. E is the sister of A. F is the son of C. How is D related to F?
In a family, there are three generations. X is the grandfather of Y. Y has two siblings, Z and W. W is married to V, who is the daughter of U. How is U related to X?