question: Which writer of M0 married M1 's child
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:film.writer.film M0 .
  ?x0 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses ?x1 .
  ?x1 ns:people.person.parents|ns:fictional_universe.fictional_character.parents|ns:organization.organization.parent/ns:organization.organization_relationship.parent M1 .
  FILTER ( ?x0 != ?x1 )
  }