diff --git a/tests/test_arg_category.py b/tests/test_arg_category.py
index 99376d7..cf976c3 100644
--- a/tests/test_arg_category.py
+++ b/tests/test_arg_category.py
@@ -71,3 +71,10 @@ def test_drug_to_drug_classes():
     ]
     for t, e in zip(test_cases, expected_output):
         assert drugs_to_drug_classes(t) == e
+
+
+def test_multiple_parents():
+    # ARO:3000130 has multiple parents
+    edeine_A = _assert_aro_name('ARO:3000130', 'edeine A')
+    assert drugs_to_drug_classes([edeine_A]) == [_assert_aro_name('ARO:3000053', 'peptide antibiotic')]
+