parent(pam,bob).
parent(tom,bob).
parent(tom,liz).
parent(bob,ann).
parent(bob,pat).
parent(pat,jim).

male(bob).
male(jim).
male(pat).
male(tom).
female(pam).
female(liz).
female(ann).

brother(X,Y) :-  male(X),parent(Somebody,X),parent(Somebody,Y), X \= Y.
father(X,Y) :- male(X),parent(X,Y).
mother(X,Y) :- female(X),parent(X,Y).
son(X,Y) :- male(X),parent(Y,X).
daughter(X,Y) :- female(X),parent(Y,X).
grandfather(X,Y) :- male(X),parent(X,Somebody),parent(Somebody,Y).
aunt(X,Y) :- female(X),sister(X,Mom),mother(Mom,Y).
aunt(X,Y) :- female(X),sister(X,Dad),father(Dad,Y).
sister(X,Y) :- female(X),parent(Par,X),parent(Par,Y), X \= Y.
uncle(X,Y) :- brother(X,Par),parent(Par,Y).
cousin(X,Y) :- uncle(Unc , X),father(Unc,Y).