# Logic puzzle to prove which relative is male or female?

C, D, E, F, G, H, and I are the father, mother, aunt, brother, sister, wife and daughter of J, but you do not know which is which. But you know that:

• E and F are the same gender.
• C and D are of different genders.
• H was born before C
• F is not the mother of J.

Referring to the above information, which one of the following must be true?

• C is female.
• D is female.
• E is female.
• F is male.
• H is male.
• I've spent an hour staring at this puzzle so far - I'm utterly stuck. Even a clue would be much appreciated. – Contango Jun 12 '13 at 9:13

See there are two males among the $7$ persons.
Consider that $E,F$ are males then except $E,F$ all must be females so $C,D$ cannot be of different genders which contradicts the hypothesis so $E,F$ must be females.Thus third option that $E$ is female is necessarily true.