This article looks at the conditions of emergence of play and denial in a child's treatment. Denial, as Freud introduced it in his 1925 article, essentially combines three terms, one of which is the transference address while the other two are in conflict. In this treatment, hatred and agitation were in the foreground. It was from the moment rejection was expressed directly that the address appeared, making it possible to take the two conflicting terms into consideration. Play and intellectual curiosity in the form of an interest in mechanics could then emerge in the treatment and with the analyst. However, the judgement of reality remained precarious and needed to be reestablished in the analyst by means of a work on negation within herself aimed at refinding the object of an address in order to get in contact with her own countertransference movements through this work of negation.