Did M2 star M1 's child 's sibling and star M0 's spouse
SELECT count(*) WHERE {
?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 M0 .
?x1 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 .
?x2 ns:people.person.parents|ns:fictional_universe.fictional_character.parents|ns:organization.organization.parent/ns:organization.organization_relationship.parent M1 .
FILTER ( ?x0 != M0 ) .
FILTER ( ?x1 != ?x2 ) .
M2 ns:film.film.starring/ns:film.performance.actor ?x0 .
M2 ns:film.film.starring/ns:film.performance.actor ?x1
}