Julie's Mom has five daughters.
You probably said "Junu" because that would logically be the next name in the sequence and we naturally assume the question is about guessing the next name in the sequence. So we miss the fact that the questioner did not actually name the mother, but instead described her as belonging to one of the daughters and one not in the list. Ergo, logically, Julie's Mom must have a fifth daughter named Julie.
I've written a lot about propaganda and deception lately. This word trick is an interesting peek at how someone gets you looking one way so that you miss what's really going on.
The numbered list pulled your eyes away from the key bit of information you needed to solve the puzzle which was in the first line. We read past this line because Julie was a modifier of Mom and you don't pay as much attention to modifiers as you do to the nouns modified and the verbs in sentences. You'd have guessed it easily if the questioner had said "Julie has four sisters, name the fifth one," and then been given the list. Even then, you might have taken a whack at the sequence because it was new and intriguing information and our brains are drawn to the new and unknown. Everything else gets shoved into the background (such as the information that the mother of the four girls in the list was also Julie's mother).
This trick takes advantage of our trust that the person talking to us isn't lying to us or trying to deceive and our fascination with new stuff. That's why presidential press secretaries say, "That happened a long time ago," when they really don't want to talk about something.
That's why presidents bomb aspirin factories when they want someone to not notice they've been hitting on the interns. That's why the guys in the White House gave up the IRS and the Justice Department - anything to get you looking away from the hearings about Benghazi. Better the press looks at naughty subordinates than at the big guy.
Bad people always want to draw your attention away from the really nasty bits that are going on right before your eyes. And because people are trusting we are fooled. It happens in families, It happens in politics and it happens in the spiritual world. The devil does slight of hand and if we're careful he'll get us looking one way when we ought to be looking the other. People are embarrassed when they are caught like that and fooled, but they oughtn't be.
There is no shame on those who are tricked.
The shame is on those who do the trickery.
I'm just saying.
Tom King (c) 2013