SQL & PL/SQL :: Removing Duplicate In Hierarchy Level

I have requirement to suppress the duplicate nodes on same level in hierarchy query.
Below given is the script for it.

CREATE TABLE NODE_LVL (PARENT_NODE VARCHAR2(100), CHILD_NODE VARCHAR2(100));

INSERT INTO NODE_LVL VALUES('TBL_APL','TBL_AFL');
INSERT INTO NODE_LVL VALUES('TBL_APP','TBL_ACS');
INSERT INTO NODE_LVL VALUES('TBL_ADD','TBL_ADW');
INSERT INTO NODE_LVL VALUES('TBL_ADP','TBL_ADV');
INSERT INTO NODE_LVL VALUES('TBL_AOP','TBL_AOV');
[code]......

Table 'TBL_APP' is having 2 parent nodes i.e 'TBL_AOV' and 'TBL_ADV'
SELECT * FROM node_lvl WHERE child_node = 'TBL_APP';

At level 5 there is duplicate nodes i.e 'TBL_APP' and 'TBL_ACS' as parent_node and child_node respectively.

SELECT PARENT_NODE, CHILD_NODE, LEVEL FROM NODE_LVL START WITH PARENT_NODE = 'TBL_ACF' CONNECT BY PRIOR CHILD_NODE = PARENT_NODE;

I want to suppress such duplicates. So I added DISTINCT

SELECT DISTINCT PARENT_NODE, CHILD_NODE, LEVEL FROM NODE_LVL START WITH PARENT_NODE = 'TBL_ACF' CONNECT BY PRIOR CHILD_NODE = PARENT_NODE;

BUT requirement is to maintain the same order (of hierarchy) as it was before adding DISTINCT.