There are six persons A, B, C, D, E and F. C is the

Solution

C is the sister of F. This means C and F are siblings. B is the brother of E's husband. This implies E's husband has a brother named B. D is the father of A and grandfather of F. D is both A's father and F's grandfather, meaning A must be one of F's parents. There are two fathers, three brothers, and a mother in the group. D is one of the fathers. There is one more father, who must be F's father, i.e., A. The three brothers include B, F, and potentially A (if A is male). There is a mother, which must be E, the wife of A. Conclusion: A is E's husband since he is the son of D, the father of F, and fits all conditions.  Therefore, E's husband is A.