In early social pretend play, the development of mental representations can be studied both in the child’s play and in communicative behavior. A girl was observed from the age of 18 to 32 months during pretend play with an adult. The child’s requests to share her play with the adult during a specific pretend play format were noted and the child’s communicative and cognitive performances were analyzed. The child’s play behavior and her uses of language were found to be related to the development of her capacities of representation. A communicative use of pretend gestures was identified, together with a developmental shifting of the reciprocal roles of gestures and language expressing the child’s pretend activities. A close relationship between the child’s communicative and representational abilities appeared to emerge.