diff --git a/db/newsgroup.sql b/db/newsgroup.sql
index 5f18afe..fc86142 100644
--- a/db/newsgroup.sql
+++ b/db/newsgroup.sql
@@ -12,6 +12,7 @@ create table newsgroup_message (
     created_on   DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
     newsgroup_id INTEGER NOT NULL,
     message_id   TEXT NOT NULL UNIQUE,
+    parent_id    TEXT,
     sender       TEXT NOT NULL,
     subject      TEXT NOT NULL,
     content      TEXT NOT NULL,
diff --git a/lib/nntp/tiny/message.py b/lib/nntp/tiny/message.py
index 58c3568..1d345ce 100644
--- a/lib/nntp/tiny/message.py
+++ b/lib/nntp/tiny/message.py
@@ -24,14 +24,24 @@ class MessageState(enum.Enum):
     BODY   = 2
 
 class Message(DatabaseTable):
-    __slots__ = 'newsgroup_id', 'state', 'headers', 'line', 'content', 'body', '_key',
+    __slots__ = (
+        'id',
+        'newsgroup_id',
+        'state',
+        'headers',
+        'line',
+        'content',
+        'body',
+        '_key'
+    )
 
     name    = 'newsgroup_message'
     key     = 'id'
     columns = (
         'newsgroup_id',
-        'message_id',
         'created_on',
+        'message_id',
+        'parent_id',
         'sender',
         'subject',
         'content'
@@ -41,6 +51,7 @@ class Message(DatabaseTable):
     RE_MESSAGE_ID = re.compile(r'^<([^<>]+)>$')
 
     def __init__(self):
+        self.id           = None
         self.newsgroup_id = None
         self.state        = MessageState.EMPTY
         self.headers      = dict()
@@ -52,6 +63,7 @@ class Message(DatabaseTable):
     @staticmethod
     def __from_row__(row):
         message = Message()
+        message.id = row['id']
         message.parse(row['content'])
 
         return message
@@ -59,8 +71,9 @@ class Message(DatabaseTable):
     def __values__(self):
         return (
             self.newsgroup_id,
-            self.id(),
             self.date(),
+            self.unique_id(),
+            self.header('references'),
             self.sender(),
             self.subject(),
             self.content
@@ -96,7 +109,7 @@ class Message(DatabaseTable):
     def header(self, key: str):
         return self.headers.get(key.lower())
 
-    def id(self) -> str:
+    def unique_id(self) -> str:
         match = self.RE_MESSAGE_ID.match(self.header('Message-ID'))
 
         return match[1]