5 Things Arya May Do After Reading Sansa's Letter

The direct approach is probably too much to hope for, but Arya may take the scroll directly to Sansa and ask her why she wrote it. This could save the Stark sisters so much heartache in the long run. If Sansa has a chance to explain to Arya that she had no choice in the matter, they could move on to discussing bigger problems like how to bring down the snake that is Littlefinger.