diff --git a/lib/selectors/chat-selectors.js b/lib/selectors/chat-selectors.js
--- a/lib/selectors/chat-selectors.js
+++ b/lib/selectors/chat-selectors.js
@@ -26,6 +26,7 @@
   type MessageInfo,
   type MessageStore,
   type ComposableMessageInfo,
+  type ReactionMessageInfo,
   type RobotextMessageInfo,
   type LocalMessageInfo,
   messageTypes,
@@ -272,6 +273,7 @@
   endsCluster: boolean,
   +robotext: string,
   +threadCreatedFromMessage: ?ThreadInfo,
+  +reactions?: $ReadOnlyArray<ReactionMessageInfo>,
 };
 export type ChatMessageInfoItem =
   | RobotextChatMessageInfoItem
@@ -283,6 +285,7 @@
       +startsCluster: boolean,
       endsCluster: boolean,
       +threadCreatedFromMessage: ?ThreadInfo,
+      +reactions?: $ReadOnlyArray<ReactionMessageInfo>,
     };
 export type ChatMessageItem = { itemType: 'loader' } | ChatMessageInfoItem;
 const msInFiveMinutes = 5 * 60 * 1000;
@@ -304,6 +307,21 @@
       ? sortMessageInfoList([...threadMessageInfos, ...additionalMessages])
       : threadMessageInfos;
 
+  const reactionsMap = new Map<string, Array<ReactionMessageInfo>>();
+
+  for (let i = 0; i < messages.length; i++) {
+    const messageInfo = messages[i];
+    if (messageInfo.type !== messageTypes.REACTION) {
+      continue;
+    }
+
+    if (reactionsMap.has(messageInfo.targetMessageID)) {
+      reactionsMap.get(messageInfo.targetMessageID)?.push(messageInfo);
+    } else {
+      reactionsMap.set(messageInfo.targetMessageID, [messageInfo]);
+    }
+  }
+
   const chatMessageItems = [];
   let lastMessageInfo = null;
   for (let i = messages.length - 1; i >= 0; i--) {
@@ -358,6 +376,12 @@
       );
       const localMessageInfo =
         messageStore.local[messageKey(originalMessageInfo)];
+
+      let reactions;
+      if (originalMessageInfo.id) {
+        reactions = reactionsMap.get(originalMessageInfo.id);
+      }
+
       chatMessageItems.push({
         itemType: 'message',
         messageInfo: originalMessageInfo,
@@ -366,6 +390,7 @@
         startsCluster,
         endsCluster: false,
         threadCreatedFromMessage,
+        reactions,
       });
     } else {
       invariant(
@@ -386,6 +411,7 @@
         endsCluster: false,
         threadCreatedFromMessage,
         robotext,
+        reactions: reactionsMap.get(originalMessageInfo.id),
       });
     }
     lastMessageInfo = originalMessageInfo;