diff --git a/src/matrix/room/timeline/entries/BaseEventEntry.js b/src/matrix/room/timeline/entries/BaseEventEntry.js
index b3ac3e9c..884bffa9 100644
--- a/src/matrix/room/timeline/entries/BaseEventEntry.js
+++ b/src/matrix/room/timeline/entries/BaseEventEntry.js
@@ -18,7 +18,7 @@ import {BaseEntry} from "./BaseEntry";
 import {REDACTION_TYPE} from "../../common.js";
 import {createAnnotation, ANNOTATION_RELATION_TYPE, getRelationFromContent} from "../relations.js";
 import {PendingAnnotation} from "../PendingAnnotation.js";
-import {createReplyContent} from "./reply.js"
+import {createReplyContent, THREADING_REL_TYPE} from "./reply.js"
 
 /** Deals mainly with local echo for relations and redactions,
  * so it is shared between PendingEventEntry and EventEntry */
@@ -36,7 +36,7 @@ export class BaseEventEntry extends BaseEntry {
     }
 
     get isThread() {
-        return this.relation?.["rel_type"] === "io.element.thread";
+        return this.relation?.["rel_type"] === THREADING_REL_TYPE;
     }
 
     get isRedacting() {
diff --git a/src/matrix/room/timeline/entries/reply.js b/src/matrix/room/timeline/entries/reply.js
index bbb2d53d..2fbbd0d4 100644
--- a/src/matrix/room/timeline/entries/reply.js
+++ b/src/matrix/room/timeline/entries/reply.js
@@ -14,6 +14,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+import {getRelatedEventId} from "../relations.js";
+
+export const THREADING_REL_TYPE = "io.element.thread";
+
 function htmlEscape(string) {
     return string.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
 }
@@ -81,8 +85,8 @@ function createThreadContent(entry, msgtype, body) {
         msgtype,
         body,
         "m.relates_to": {
-            "rel_type": "m.thread",
-            "event_id": entry.id 
+            "rel_type": THREADING_REL_TYPE,
+            "event_id": getRelatedEventId(entry)
         }
     };
 }