question: What sibling of a costume designer did M1 's sibling 's employer employ
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company ?x1 .
  ?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 ?x2 .
  ?x1 ns:business.employer.employees/ns:business.employment_tenure.person ?x3 .
  ?x2 a ns:film.film_costumer_designer .
  ?x3 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 M1 .
  FILTER ( ?x0 != ?x2 ) .
  FILTER ( ?x3 != M1 )
  }