["My sister is really sick right now with a fever. I've been taking care of her day and night for the last week.", "Are't you afraid to catch the fever?", 'Not really. I tend to be rather healthy and not get sick even if others around me are sick.']
Good for you, I hope your sister gets well too.
I've been taking care of my sick sister for the last week. She has a really bad fever and it's very difficult for us.