question: Did M2 and M4 star M1 's Mexican spouse 's sibling and star M3
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 ?x1 .
  ?x1 ns:people.person.nationality ns:m.0b90_r .
  ?x1 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses M1 .
  FILTER ( ?x0 != ?x1 ) .
  FILTER ( ?x1 != M1 ) .
  M2 ns:film.film.starring/ns:film.performance.actor ?x0 .
  M2 ns:film.film.starring/ns:film.performance.actor M3 .
  M4 ns:film.film.starring/ns:film.performance.actor ?x0 .
  M4 ns:film.film.starring/ns:film.performance.actor M3
  }