Pointing to a boy, Mrs. Mira said, He is the only son of my grandfather's only child. How is the boy related or Mrs. Mira?
(1) Cousin
(2) Uncle
(3) Sister
(4) Brother
(5) Cannot be determined

• Mira's Grandfather G
  G's only child C
  Therefore C is one of the parent of Mira
  And the boy is son of C.
  Therefore Mira and the boy are siblings. Hence 4) brother
• 7 years agoHelpfull: Yes(2) No(0)