In this study, relations between emotional resonance responses to another's distress, emotion regulation, and self-other discrimination were investigated in infants three-, six-, and nine-months-old. We measured the emotional reactions to the pain cry of a peer, along with the ability to regulate emotions and to discriminate between self and other body movements. We found evidence that infants do regulate their emotional resonance responses to another's distress. This relation is age specific, with younger infants using more primitive self-soothing behaviors, while in older participants attentional based strategies relate to affect sharing reactions. Only nine-month-old infants have shown self-other differentiation abilities, and these were significantly connected to their emotions in response to a peer's distress. These findings have implications for our understanding of early empathy development.