diff --git a/tests/serialize/test_io.py b/tests/serialize/test_io.py
index 1881e7486..a64d0cabc 100644
--- a/tests/serialize/test_io.py
+++ b/tests/serialize/test_io.py
@@ -22,3 +22,19 @@ def test_read_write(EN):
 
     assert r1.string == doc1.string
     assert r2.string == doc2.string
+
+
+@pytest.mark.models
+def test_left_right(EN):
+    orig = EN(u'This is a simple test. With a couple of sentences.')
+    result = Doc(orig.vocab).from_bytes(orig.to_bytes())
+
+    for word in result:
+        assert word.head.i == orig[word.i].head.i
+        if word.head is not word:
+            assert word.i in [w.i for w in word.head.children]
+        for child in word.lefts:
+            assert child.head.i == word.i
+        for child in word.rights:
+            assert child.head.i == word.i
+