How did Killua not know Nen

[Snape Uchiha]

One thing that has been bothering me is how come Killua didn't know Nen until he was 12. If you look at Killua's family, it really makes no sense.

1) Kalluto, Killua's youngest brother (yes, he's a boy) was taught nen by his parents when he was younger than 12 and he is good enough to be on the Phantom Troupe. If Killua was supposed to be the best assasin in his family, why was he not taught nen?

2) From later in the manga

Spoiler

Alluka had a nen power when he was a little kid. Let's assume he was born with with it and his parents didn't teach it to him. Killua knew about it. He knew all of the conditions to Alluka's power. So how could he know this and still not know of the existence of nen?

 

[The7thHokage]

Lets keep it at they forgot to teach him or something, I dont want a plot hole in this perfect story :|

 

[Sir Blades]

Well he is the least liked in the family other than his younger brother. It could be that he knew the basics but just didnt know the exact terminology or accurate usage of it.

Its like saying that you know a rocket uses rocket fuel and has fuel tanks, but you dont know how the fuel is made, where the tanks are located and how to start the rocket. He had a vague or general understanding of abilities.

 

[Meekz89]

Illumi was his main teacher, But illumi wants to be the head of the Family being the oldest son. Leading him to try and control Killua and not training the best he could. Killua was suppose to learn Nen the first time on the 200th floor

 

[Fair Warning]

Also how did Killua know

Spoiler

That Dragon Dive was Zeno's technique? Even if he did see it when younger, he couldnt see the Nen because you have to use Gyo.

 

[Sakura Saluja]

Also how did Killua know

Spoiler

That Dragon Dive was Zeno's technique? Even if he did see it when younger, he couldnt see the Nen because you have to use Gyo.

Because of his nice instincts? -.-