Even if she one day got the ability to display her emotions on her face more clearly, she needed a way to be able to properly control them or to at least mask her emotions.
If there was anything that Skin Walkers were then they took on the appearances of others but that was not all.
Skin Walkers took the voice of the person too and it could be said that they did their best to take on the life of that person too.
They had to learn about each person they transformed into so that they could perform as best as they could.
Even the most perfect of disguises could be seen through by people who knew that person well enough and could sense that something was off.
If there was ever a time that she was asked something that a person she was transformed as should know well enough and she did not know anything about it, it was just yet another way to create doubts in the minds of people around her.
