diff --git a/lib/shared/messages/update-relationship-message-spec.js b/lib/shared/messages/update-relationship-message-spec.js
--- a/lib/shared/messages/update-relationship-message-spec.js
+++ b/lib/shared/messages/update-relationship-message-spec.js
@@ -62,6 +62,17 @@
         | UpdateRelationshipMessageData
         | RawUpdateRelationshipMessageInfo,
     ): string {
+      if (
+        data.type === messageTypes.UPDATE_RELATIONSHIP &&
+        data.operation === 'farcaster_mutual'
+      ) {
+        return JSON.stringify({
+          operation: data.operation,
+          targetID: data.targetID,
+          creatorFID: data.creatorFID,
+          targetFID: data.targetFID,
+        });
+      }
       return JSON.stringify({
         operation: data.operation,
         targetID: data.targetID,