diff --git a/Objects/structseq.c b/Objects/structseq.c
index f6d7019789b1ff7..d772b16e815cc73 100644
--- a/Objects/structseq.c
+++ b/Objects/structseq.c
@@ -510,16 +510,21 @@ _PyStructSequence_InitBuiltinWithFlags(PyTypeObject *type,
                                        PyStructSequence_Desc *desc,
                                        unsigned long tp_flags)
 {
+    PyMemberDef *members;
+    Py_ssize_t n_members, n_unnamed_members;
+
     if (type->tp_flags & Py_TPFLAGS_READY) {
         if (_PyStaticType_InitBuiltin(type) < 0) {
             goto failed_init_builtin;
         }
+        n_members = count_members(desc, &n_unnamed_members);
+        if (initialize_structseq_dict(
+                desc, _PyType_GetDict(type), n_members, n_unnamed_members) < 0) {
+            return -1;
+        }
         return 0;
     }
 
-    PyMemberDef *members;
-    Py_ssize_t n_members, n_unnamed_members;
-
     members = initialize_members(desc, &n_members, &n_unnamed_members);
     if (members == NULL) {
         return -1;