I feel that my sister is taking the best decision as the way she wants to live her life depends absolutely on her wishes. But also it has its own demerits. It brings up the rising cost of living problem. So she might have to face a lot of hard times probably.
Alert: I am writing from my view!!-

Let's start this with a question: What happens when your dreams and other's  expectations about you clash with each other? Ever thought of that! Well, i haven't until i read the question! 

When it come to the dream you chose, it is a part of who you are!
It is not easy to select between 10 of your favorite outfits, isn't it? Then what's the difference when it gets to dreams? To chose is easy; but to chose the perfect one is always hard!

your elder sister, from my opinion; had chose from her heart! She learned pottery as a hobby fro college but from taking it up as a profession she really must have devoted herself for it! She must have a good talent in pottery business too! If she can outshine other competitors, maybe she can make some profit out of it too! work means not to gain good salary but to find satisfaction in something!
But don't you see -that is only one side of the coin!

She is having more potential than she ever can imagine herself to have!
So she should never put away her career and future
And when it comes to life ans society, people never used to give preference to others if they are not having a respectable profession! 
And a good salary is required to hang around in business!  
So it's important that she continue her schooling as her parents wish! 

but pottery is something she can work out part time, right? she can take up her dream as her part time job! So she can get success in both her different professions and live inspiring others through her life!

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