Calling node delete (node_delete_multiple) is not deleting all comments from database When I do a query on the database (SELECT * FROM comment c  where c.nid = 119445765;)  I get a 12 rows in set (0.00 sec)
The I call node_delete_multiple(array(119445765)). 
Then I go back to the database and perform the same query SELECT * FROM comment c  where c.nid = 119445765;)  I get a 5 rows in set (0.00 sec).

Now These may be replies to comments since this is a forum. However, how do I ensure they are deleted? Do I have to perform the query myself? 

UPDATE:

I have stepped debug this issue here is my notes:
1. node_delete_mutliple -> invokes comment_node_delete
2. comment_node_delete perform this query $cids = db_query('SELECT cid FROM {comment} WHERE nid = :nid', array(':nid' =&gt; $node-&gt;nid))-&gt;fetchCol(); and it correctly returns  all cids  associated with the node.
3. comment_node_delete calls comment_delete_multiple which in turns calls $comments = comment_load_multiple($cids); NOW comment_load_multiple($cids); is not returning the correct number of comments. Surprisingly it is always ommiting comments by a certain user.

I am continuing to debug and will add more info,

Update 2

 $cids = db_query('SELECT cid FROM {comment}
 WHERE nid = :nid', array(':nid'  =&gt; 119318471))-&gt;fetchCol();
 dpm($cids); // Gives the correct number of $cids
 $comments = entity_load('comment', $cids, $conditions = array(), TRUE);
 dpm($comments); // Is an array with fewer comments than number of $cids


So the problem so far is in entity_load. 

Note I failed to mention that the database is migrated from another system and may contain some bad references.
you should check the watchdog table to see if there are any errors. The function calls comment_delete_multiple and with in that functions deletes all the replies as well. 

If there was any error during this process it would rollback to a specific point in this case I guess it would be during the delete process of child comments. Tne information would be stored in the watchdog table with type set to comment. This would give you a hint as to why it was not deleted.