Do you know how many times I was told "No." And told I can't model. Even after a modeling job recently with a top brand the makeup artist said to me, " models who are 5'6" and shorter do not work."
I just roll my eyes. There is plenty of work for a shorter girl. Yes being proportioned helps, and you will not be in the fashion world, but not being a tall Giraffe is not going to stop me from going after what I want.
I set realistic goals for myself. It's not like I am trying to walk the catwalk. But there is so much for a shorter girl to consider and chase:
Beauty modeling and parts modeling, and commercial print modeling is the area a shorter girl can work in.
She does need to understand it will be a challenge and that the modeling business is not what you might see on tv. One agent, might not help you get started, you will need to work with many, freelancing as a model. Working with commercial print modeling agencies and building your portfolio.
The more you chase realistic things, and legit agents, and modeling jobs, the more of a model you will be. Social sites will not cut it. You will not be a model because someone thinks your hot, modeling, really modeling, involves thinking about the business from a business mindset. If you let yourself believe you are not good enough for something, then you won't be. If you try, and chase what you want in a realistic way, you will most likely prove everyone wrong.