Riddle: Someone’s mother has four sons; three are named North, East and West. What’s the name of the fourth son?
Answer: From question the name of the fourth son of the mother mentioned in the question is someone.
According to the given question the mother has four sons and it is mentioned that someone’s mother.
Names of three sons of her mother are north, west and South.
So according to the the first line of the question someone’s mother obviously the name of the fourth son will be someone.