The probable relationship between the two speakers is doctor and ______.

Doctor:. Well, there’s not much you can do about the flu, you know. The best thing you can do is to stay home. It’s best to stay away from other people, so why don’t you take a couple of days off from work?
Kevin: Yes, I will. And do you think I should stay in bed and rest?
Doctor: It’s not really necessary to go to bed. Just as long as you stay indoors and rest. You know, watch TV or read.
Kevin: I see. Nothing too active, huh? And is it a good idea to drink a lot?
Doctor: Yes, you need to drink lots of liquids. That’ll help. Now you won’t feel very hungry. But when you do eat, just eat a little. Don’t have a big meal. That way it’ll be easier to rest.
Kevin: OK. Are you going to give me a prescription?
Doctor: No, I’m afraid there’s no medicine for the flu. You just have to rest and wait for it to go away. Medicine won’t really do any good.
Kevin: How about aspirin for the aches?
Doctor: Sure. Sometimes aspirin helps. Anyway, it can’t do any harm. Take one every four hours.
Kevin: All right. Thank you, doctor.
Doctor: Call me in a few days if you don’t feel better.
Kevin: I will. Bye.