What the...?

I have a job opportunity which would mean a significant promotion and salary increase. I would have to move, but I would only be about 30 miles farther away from my parents. They are getting older. My dad has leukemia, but is in remission. My sister had the nerve to tell me that she thinks this job is too far away and that she worries about our parents and that they would need me and I would be too far away. She only lives 8 miles from them, has no children and only works 4 days a week. Couldn't she be there if needed? Why does it all fall to me? She is their first-born, actually they're only born since I am adopted. I won't be made to feel guilty for thinking about my future. I'm not married and have to think about my financial security. She is married and has her house paid off. Isn't family just lovely?