question: Did M4 star M5 and M6 and star a Italian person 's American female sibling
query: SELECT count(*) WHERE {
  ?x0 ns:people.person.gender ns:m.02zsn .
  ?x0 ns:people.person.nationality ns:m.09c7w0 .
  ?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 a ns:people.person .
  ?x1 ns:people.person.nationality ns:m.03rjj .
  FILTER ( ?x0 != ?x1 ) .
  M4 ns:film.film.starring/ns:film.performance.actor ?x0 .
  M4 ns:film.film.starring/ns:film.performance.actor M5 .
  M4 ns:film.film.starring/ns:film.performance.actor M6
  }