Which sibling of a character was a parent of M0
SELECT DISTINCT ?x0 WHERE {
?x0 ns:people.person.children|ns:fictional_universe.fictional_character.children|ns:organization.organization.child/ns:organization.organization_relationship.child M0 .
?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:fictional_universe.fictional_character .
FILTER ( ?x0 != ?x1 )
}