Despite use of terms such as “siblings” or “brothers from the same mother (India)”, there have been few or no attempts to explain the wide-ranging sentiments associated with India-Pakistan rivalry from a theoretical perspective. A cross-disciplinary approach has been employed in this article to re-examine and reconceptualize the existing landscape of Pakistan-India conflict. An interpersonal conflict model has been used to theorize the emotions found in their bilateral relations which have often been neglected or marginalized while studying their obsessive rivalry with each other. Despite testing the troublesome dyad of these nation-states on diametrically opposite ethnic or religious grounds, this article categorizes Pakistan and India as former family members who parted ways in 1947. The article explains different phases of an interpersonal conflict model and clarifies how the emotional climate associated with these phases could be transposed to intergroup and interstate levels of conflicts between communities who lived together for centuries, and engage them in a perpetual rivalry.