Did M2 star a Mexican screenwriter 's parent and star M3 and M4
SELECT count(*) WHERE {
?x0 ns:people.person.children|ns:fictional_universe.fictional_character.children|ns:organization.organization.child/ns:organization.organization_relationship.child ?x1 .
?x1 a ns:film.writer .
?x1 ns:people.person.nationality ns:m.0b90_r .
M2 ns:film.film.starring/ns:film.performance.actor ?x0 .
M2 ns:film.film.starring/ns:film.performance.actor M3 .
M2 ns:film.film.starring/ns:film.performance.actor M4
}