I'm a novice but hopefully this can be of some help.
Past-King of Cups - Indicates worrying, crankiness and a feeling of lack of support; fearing the worst; dr. appt. happened?
Present - Page of Wands - will need attention; upset stomach
Future - King of Wands - many wands suggest a stage of development; tension headaches, lower backaches; new treatment or exercise regiment to be suggested; be self-confident
I think that depending on the severity of whatever is ailing your sister, you may want to think about a different spread, or as Gem said, rephrasing the question. I think you have 2 options: very vague, such as how do I improve my health or very specific how do I deal with [insert condition]?
I admit I got most of this from a book I
always use and trust......but the self-confident part........I think is essential in any of life's trials.
Gem brought up an interesting point also about how maybe this has more to do with a personality trait than an actual illness.