question: Was M1 produced by a actor 's parent '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 ?x1 .
  ?x1 ns:people.person.children|ns:fictional_universe.fictional_character.children|ns:organization.organization.child/ns:organization.organization_relationship.child ?x2 .
  ?x2 a ns:film.actor .
  FILTER ( ?x0 != ?x1 ) .
  M1 ns:film.film.produced_by|ns:film.film.production_companies ?x0
  }