The effects of level of interpersonal attraction (or friendship) on young children's language production were examined during a 15-minute play episode, in which 40 pairs of 3-5 year-olds were separated and then reunited. Friendship was measured by a picture sociometric test validated against free play choices. Language measures focused on structure (MLU, number of utterances, and pause length) and contents using a modified form of the Gottman and Parkhurst coding system. Both aspects of linguistic production were affected by friendship and by stage of play episode (initial five minutes, separation, reunion). In general, separation dampened language, particularly those aspects, such as questions, most dependent upon partner presence, while reunion stimulated language production above baseline levels. Friendship interactions showed that children with friends initially engaged in more fantasy play and paused longer between utterances than when with non-friends. Only with friends did fantasy play decline during separation and exceed baseline levels during reunion. In addition, for this group, number of utterances increased during reunion. (Author/MP)