Were M1 and M3 employed by a screenwriter 's parent 's employer and employed by M2
SELECT count(*) WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?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.writer .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
M3 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
M3 ns:people.person.employment_history/ns:business.employment_tenure.company M2
}