diff --git a/lib/models/room.js b/lib/models/room.js
index 46c07fb90..03fd00722 100644
--- a/lib/models/room.js
+++ b/lib/models/room.js
@@ -250,8 +250,10 @@ Room.prototype.addEventsToTimeline = function(events, toStartOfTimeline) {
             stateContext.setStateEvents([events[i]]);
             // it is possible that the act of setting the state event means we
             // can set more metadata (specifically sender/target props), so try
-            // it again if the prop wasn't previously set.
-            if (!events[i].sender) {
+            // it again if the prop wasn't previously set. It may also mean that
+            // the sender/target is updated (if the event set was a room member event)
+            // so we want to use the *updated* member (new avatar/name) instead.
+            if (!events[i].sender || events[i].getType() === "m.room.member") {
                 setEventMetadata(events[i], stateContext, toStartOfTimeline);
             }
         }