Good points raised by DPG and Richiev.
The character flaw in many fantasy movies is normally a cliche and waters down the impact of the journey. I think that both DPG and Richiev's suggestions put together are the better option only after she learns her lesson and completes her inner journey is she able to save her brother.
Karel Segeres mentioned the order of the inner and outer goal achievements needing to be that only after the MC achieves the inner goal and completes their arc are they allowed to achieve the outer goal as a reward.
Basically what this means is that achieving the outer journey's goal is a feat and raises its significants, significantly.