// stats for the further receiver's message
function (cb) {
messageStatService.updateMessageStat(receiverMessage, cb);
},
// stats for the further receiver's message
function (cb) {
messageStatService.updateMessageStat(firstReply, cb);
},
// update stats with another initiator's message
function (cb) {
messageStatService.updateMessageStat(initiatorMessage, cb);
},