What is the difference between Affection and Affectation?

What is the difference between Affection and Affectation? : 
Affection : 

( 1 ) Love – feeling of fondness

He felt great affection for his sister. 

He tried to win her affection. 

Have you affection for your children? 

Affectation : 

( 1 ) Unnatural behaviour, manner of speaking intended to impress others

I detest all affectations. 

His little affectation irritated her. 

( 2 ) Pretence, deliberate display of gestures that are not truly felt

His affectation while singing really gets on my nerves.