If you aren't sure that what you are doing is feeling good to the sick person, ask them. Let them know that it's okay to tell you the truth. You want to care.
Whose as an interrogative pronoun is used to ask about someone's or something's possession. It replaces possessive determiners and the following noun or.
A preposition is a word—and almost always a very small, very common word—that shows direction (to in "a letter to you"), location (at in "at the door"), or time.