Before revision:  We compute the optimal ratio of senior to junior debts, which we call the optimal seniority ratio, for two uncorrelated Erd\H{os-R\'{e}nyi }  networks.
After revision:  We compute the optimal ratio of senior to junior debts, which we call the optimal seniority ratio, for two uncorrelated Erd\H{os-R\'{e}nyi } Erdos-Renyi networks.