The Interpretation of Dreams by Sigmund Freud Chapter 4 Page 34

I can count with a large degree of certainty upon causing such a dream after I have once explained to the patient my theory that the dream is a wish-fulfillment.

5 I may even expect this to be the case in a dream merely in order to fulfill the wish that I may appear in the wrong. The last dream which I shall tell from those occurring in the course of treatment again shows this very thing. A young girl who has struggled hard to continue my treatment, against the will of her relatives and the authorities whom she had consulted, dreams as follows: She is forbidden at home to come to me any more. She then reminds me of the promise I made her to treat her for nothing if necessary, and I say to her: “I can show no consideration in money matters.”

It is not at all easy in this case