Question: What are the names of the siblings of the inventor of the telephone?
Answer(s):
answer: Melville James Bell
answer: Edward Charles Bell

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ?c)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:law.inventor.us_patents ns:m.07cx4 . 
?c ns:people.person.sibling_s ?y .
?y ns:people.sibling_relationship.sibling ?x .
}