(Spoilers Extended) Sansa And Arya Prisoner's Dilemma

Here's the thing...after the trials and tribulations the Stark children have faced, I have no doubt they now realize the value of family, of someone you can trust more than ever.

On the other hand, the very fact that these children, particularly Sansa and Arya, have witnessed the ugliest facets of the world will make them wary of trusting anyone even their own blood.

a) Sansa witnessed deceit of the highest orders, first when Joffrey had Ned killed after explicitly promising to show mercy. Thereafter, she had the rose colored glasses removed after bearing cruelties from her in laws and betrothed.

Arya, a mere 10 year old, had to survive on her wits - the only way to do so by distrusting anyone and everyone around her - the brotherhood, the hound, the faceless men.

b) Secondly, these two know nothing about the other for the last 5 years . The last impression that Arya had of Sansa was of a girl who would lie/betray her sister to gain her pretty prince's favour (Nymeria debacle). And the last impression Sansa had of Arya was of raining on her parade (when she just started getting noticed by Price Joffrey).

Even siblings who have been together all their life would enter into conflict when the stakes are high in real life - history is littered with kings murdering their brothers, fathers and all kinds of relatives . So why do we expect Arya and Sansa reunion to be all hunky dory. It is bound to be acrimonious and filled with mistrust, united only by their common enemies, a little bit like Prisoner's Dilemma.

PS: I have found myself empathizing with Arya since the beginning and in her place I would be extremely careful before I trust Sansa again ( whom I see as power hungry) - if I ever did in the first place.