diff --git a/tests/unit_tests/pipeline/conftest.py b/tests/unit_tests/pipeline/conftest.py
index 40b2e930..9a19813e 100644
--- a/tests/unit_tests/pipeline/conftest.py
+++ b/tests/unit_tests/pipeline/conftest.py
@@ -164,6 +164,7 @@ def sample_message_event(sample_message_chain):
     event.sender = Mock()
     event.sender.id = 12345
     event.time = 1609459200  # 2021-01-01 00:00:00
+    event.message_chain = sample_message_chain
     return event