Is there any way to keep Bethany Hawke in your party for the whole campaign in Dragon Age 2?

I am on my third playthrough of Dragon Age 2 now. I am playing as a Rogue where on my previous 2 I was a mage. I was wondering if there is any way to keep your sister, Bethany, in your party/ team for the whole game. I want to know because I think she is a very good character and if Bioware left this option out then shame on them.Is there any way to keep Bethany Hawke in your party for the whole campaign in Dragon Age 2?
The loss of Bethany/Carver is a scripted event. The only control you have over it is whether they die, or if they become a Circle mage/Templar or a Grey Warden.Is there any way to keep Bethany Hawke in your party for the whole campaign in Dragon Age 2?
No, she's gone by act 2 no matter what you do. But, if she doesn't die in the deep roads she will fight with you in the final battle. In some ways it makes sense to the story that you lose your sibling, but I agree that it would have been great to keep them the whole game.