parent(maria,anna).
parent(petr,anna).
parent(maria,stepa).
parent(petr,stepa).
parent(matilda,petr).
parent(matilda,sonya).
parent(sonya,tony).

man(petr).
man(stepa).
man(tony).

woman(sonya).
woman(matilda).
woman(anna).
woman(maria).

married(petr,maria).

sister(X,Y):-(woman(Y);woman(X)),parent(Z,Y),parent(Z,X).
grandma(X,Y):-(woman(Y);woman(X)),parent(X,Z),parent(Z,Y).
grandd(X,Y):-(woman(Y);woman(X)),parent(Z,X),parent(Y,Z).
cusin(X,Y):-parent(Petr,X),parent(Sonya,Y),sister(Sonya,Petr),man(X).

aunt(X,Y):-parent(Z,Y),parent(T,X),(woman(Y),sister(Y,T);woman(X),sister(X,Z)).
niece(X,Y):-aunt(Y,X).
mother_in_law(X,Y):-woman(X),parent(X,Z),(married(Y,Z);married(Z,Y)).
daughter_in_law(X,Y):-mother_in_law(Y,X).