which noble person is also the sibling of dorothy percy, countess of northumberland?
Entity Entity
m.0dfnj m.047nln
Robert Devereux, 2nd Earl of Essex Penelope Blount, Countess of Devonshire
class class entity
royalty.noble_person people.sibling_relationship m.0c88vj
royalty.noble_person people.sibling_relationship royalty.noble_person
Noble person Sibling Relationship Dorothy Percy, Countess of Northumberland
none none none
people.sibling_relationship.sibling people.person.sibling_s
Sibling Siblings
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :royalty.noble_person . 
?x1 :type.object.type :people.sibling_relationship . 
VALUES ?x2 { :m.0c88vj } 
?x1 :people.sibling_relationship.sibling ?x0 . 
?x2 :people.person.sibling_s ?x1 . 
FILTER ( ?x0 != ?x1 && ?x0 != ?x2 && ?x1 != ?x2  )
}
}
(AND royalty.noble_person (JOIN (R people.sibling_relationship.sibling) (JOIN (R people.person.sibling_s) m.0c88vj)))