This study compared two contexts (storytelling and free-play) to analyse which context promoted more maternal references to mental states at two time points and to investigate their relationships with children's language and socioemotional outcomes. The sample comprised 91 mothers during interactions with their children (44% boys) when the children were aged 10-15 months and subsequently at 28-33 months. The mothers were asked to tell 2 stories to their children and interact with them during 5 min of free-play. At both ages, the mothers used more references to emotions, states of consciousness, causal talk and links to the children's life during storytelling and more references to desires and physiological states during free-play. At 30 months, the mothers increased their use of cognitions, emotions and causal talk and decreased their use of desires and physical expressions, although these differences were context-specific. The number of words and the mothers' use of desires at 12 months were related to the children's language at 30 months, and maternal references to desires, emotions and states of consciousness were related to the children's socioemotional skills, especially at 30 months.