Andy is father of B and Dexter is son of C. Eric is brother of A and E also has a daughter Fanny, if Cindy is sister of A then what is the relation between the Fanny, B and Dexter ?

Parent of B is Andy.
Parent of Fanny is Eric.
Parent of Dexter is Cindy.
Eric is Andy brother and Cindy is Andy sister.
Thus, Fanny, B and Dexter are cousins.