diff --git a/dbterd/adapters/algos/test_relationship.py b/dbterd/adapters/algos/test_relationship.py
index fa93fa9..0bb442a 100644
--- a/dbterd/adapters/algos/test_relationship.py
+++ b/dbterd/adapters/algos/test_relationship.py
@@ -101,4 +101,4 @@ def parse(manifest, catalog, **kwargs):
     logger.info(
         f"Collected {len(tables)} table(s) and {len(relationships)} relationship(s)"
     )
-    return (tables, relationships)
+    return (sorted(tables, key=lambda tbl: tbl.node_name), sorted(relationships, key=lambda rel: rel.name))