How to distinct column by starting from earliest/latest row with SQL query?

how can I distinct the column but the row were removed is from the earliest found/retain the last?

I have tried some ways, but all of them not worked.
below is the raw, column that I want to work with

parent_item_id
------------------------------------
9B3E7A72-D36A-42D3-A04C-186DEC409F93
942E1854-9EB4-4C19-8A1E-4FCC4953B50C
E75C7294-F0C4-4C6E-8C12-DF5FBC93FA3B
942E1854-9EB4-4C19-8A1E-4FCC4953B50C
942E1854-9EB4-4C19-8A1E-4FCC4953B50C


below is the ways I tried:

1. using the default behaviour of distinct like this.
   query:

WITH tree AS (SELECT distinct(ic.parent_item_id) FROM dbo.item_combination ic, dbo.product p WHERE ic.child_item_id != p.item_id
UNION ALL
SELECT ic.parent_item_id FROM tree t, dbo.item_combination ic WHERE t.parent_item_id=ic.child_item_id
)
SELECT DISTINCT (parent_item_id) from tree


result:

parent_item_id
--
9B3E7A72-D36A-42D3-A04C-186DEC409F93
942E1854-9EB4-4C19-8A1E-4FCC4953B50C
E75C7294-F0C4-4C6E-8C12-DF5FBC93FA3B

1. using row_number like this. but based on my logic it should change the order but why the final result is the same as way 1? query:

WITH tree AS (SELECT distinct(ic.parent_item_id) FROM dbo.item_combination ic, dbo.product p WHERE ic.child_item_id != p.item_id
UNION ALL
SELECT ic.parent_item_id FROM tree t, dbo.item_combination ic WHERE t.parent_item_id=ic.child_item_id
)
SELECT DISTINCT(parent_item_id) FROM
(
SELECT t.parent_item_id, [row_number]=ROW_NUMBER() OVER(ORDER BY (SELECT 1)) FROM tree t ORDER BY [row_number] DESC OFFSET 0 ROWS
) r
group by r.parent_item_id, r.[row_number]


result:

parent_item_id
--
9B3E7A72-D36A-42D3-A04C-186DEC409F93
942E1854-9EB4-4C19-8A1E-4FCC4953B50C
E75C7294-F0C4-4C6E-8C12-DF5FBC93FA3B


the result I want/expected is like this.

parent_item_id
--
9B3E7A72-D36A-42D3-A04C-186DEC409F93
E75C7294-F0C4-4C6E-8C12-DF5FBC93FA3B
942E1854-9EB4-4C19-8A1E-4FCC4953B50C

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