Well, no, except in the sense that it can be objectively demonstrated that it is better for your sister to die than it is for 100,000 Africans to die by just ab

Well, no, except in the sense that it can be objectively demonstrated that it is better for your sister to die than it is for 100,000 Africans to die by just about any measure of 'better' — outside of your own immediate and immutable personal preference — that you might care to name. So in that one sense, it could be argued that it might be an example of warped judgement.