Was a parent of a editor of a sequel of M0 M1
SELECT count(*) WHERE {
?x0 ns:film.editor.film ?x1 .
?x1 ns:film.film.prequel M0 .
M1 ns:people.person.children|ns:fictional_universe.fictional_character.children|ns:organization.organization.child/ns:organization.organization_relationship.child ?x0
}