question: Did M2 star M0 's sibling and star M1 's art director 's sibling
query: SELECT count(*) WHERE {
  ?x0 ns:people.person.sibling_s/ns:people.sibling_relationship.sibling|ns:fictional_universe.fictional_character.siblings/ns:fictional_universe.sibling_relationship_of_fictional_characters.siblings M0 .
  ?x1 ns:people.person.sibling_s/ns:people.sibling_relationship.sibling|ns:fictional_universe.fictional_character.siblings/ns:fictional_universe.sibling_relationship_of_fictional_characters.siblings ?x2 .
  ?x2 ns:film.film_art_director.films_art_directed M1 .
  FILTER ( ?x0 != M0 ) .
  FILTER ( ?x1 != ?x2 ) .
  M2 ns:film.film.starring/ns:film.performance.actor ?x0 .
  M2 ns:film.film.starring/ns:film.performance.actor ?x1
  }