male(tom).
male(doug).
male(mason).
male(mike).
male(josh).
male(joey).
male(james).
male(mac).
male(sam).
male(gabe).
male(raleigh).
male(sean).
male(gpa_sam).

female(marcia).
female(tracy).
female(autumn).
female(emma).
female(hannah).
female(kendra).
female(haley).
female(elizabeth).
female(kate).
female(izzy).
female(rozzy).
female(addie).
female(stacy).
female(april).
female(huldah).

is_married(tom, marcia).
is_married(doug, tracy).
is_married(mike, kenda).
is_married(james, kate).
is_married(sam, stacy).
is_married(gpa_sam, huldah).

married(A, B) :-
    is_married(A, B);
    is_married(B, A).

is_parent(tom, doug).
is_parent(tom, mike).
is_parent(tom, kate).

is_parent(gpa_sam, sam).
is_parent(gpa_sam, tracy).

is_parent(doug, mason).
is_parent(doug, autumn).
is_parent(doug, emma).
is_parent(doug, hannah).

is_parent(mike, josh).
is_parent(mike, haley).
is_parent(mike, joey).
is_parent(mike, elizabeth).

is_parent(james, izzy).
is_parent(james, rozzy).
is_parent(james, addie).
is_parent(james, mac).

is_parent(sam, april).
is_parent(sam, gabe).
is_parent(sam, raleigh).
is_parent(sam, sean).

parent(PARENT, CHILD) :-
    is_parent(PARENT, CHILD);
    is_married(HUSBAND, PARENT),
    is_parent(HUSBAND, CHILD).

father(PARENT, CHILD) :-
    male(PARENT),
    parent(PARENT, CHILD).

mother(PARENT, CHILD) :-
    female(PARENT),
    parent(PARENT, CHILD).

child(CHILD, PARENT) :-
    parent(PARENT, CHILD).

son(SON, PARENT) :-
    male(SON),
    child(SON, PARENT).

daughter(DAUGHTER, PARENT) :-
    female(DAUGHTER),
    child(DAUGHTER, PARENT).

sibling(CHILD, SIBLING) :-
    is_parent(P, CHILD),
    is_parent(P, SIBLING).

brother(CHILD, SIBLING) :-
    male(CHILD),
    sibling(CHILD, SIBLING).

sister(CHILD, SIBLING) :-
    female(CHILD),
    sibling(CHILD, SIBLING).

grandparent(GRANDPARENT, GRANDCHILD) :-
    parent(GRANDPARENT, P),
    parent(P, GRANDCHILD).

grandfather(GRANDFATHER, GRANDCHILD) :-
    male(GRANDFATHER),
    grandparent(GRANDFATHER, GRANDCHILD).

grandmother(GRANDMOTHER, GRANDCHILD) :-
    female(GRANDMOTHER),
    grandparent(GRANDMOTHER, GRANDCHILD).

grandchild(GRANDCHILD, GRANDPARENT) :-
    grandparent(GRANDPARENT, GRANDCHILD).

grandson(GRANDSON, GRANDPARENT) :-
    male(GRANDSON),
    grandchild(GRANDSON, GRANDPARENT).

granddaugther(GRANDDAUGHTER, GRANDPARENT) :-
    female(GRANDDAUGHTER),
    grandchild(GRANDDAUGHTER, GRANDPARENT).

cousin(PERSON, OTHER) :-
    grandchild(PERSON, X),
    grandchild(OTHER, X),
    \+ sibling(PERSON, OTHER).

aunt(AUNT, OTHER) :-
    female(AUNT),
    sister(AUNT, P),
    parent(P, OTHER).

descendant(PERSON, ANCESTOR) :-
    parent(ANCESTOR, PERSON) ;
    parent(ANCESTOR, X),
    descendant(PERSON, X).

ancestor(ANCESTOR, PERSON) :-
    descendant(PERSON, ANCESTOR).

related(PERSON, OTHER) :-
    descendant(PERSON, X),
    descendant(OTHER, X);
    descendant(PERSON, OTHER);
    descendant(OTHER, PERSON).