Too early to really know what will Surbhi be like, will stay as a loving protective sister or will change.
I thought todays' episode tried to show
1) The contrast between two sisters; and also showing how upbringing can mold a child. There is a difference in how Surbhi was brought up, more outgoing, more spunky; where as Soumya was always prevented from going out or interacting with anyone and also constantly being brought up with an underlying hostility. This would make anyone go into their shell
2) Bond between two sisters, and the relationship of Soumya and Nimmi.
3) The unchanged dynamics in the family that has not changed over the past 10 years. The hostility of GM and father is still there
Let's see what next week brings