The father item will be a record in the REQ table. You need to get the correct item and look at its RQ_REQ_PATH value and use it to define your select, e.g.:
SELECT * FROM REQ WHERE RQ_REQ_PATH LIKE 'AAAAABABC%'
The "%" is the wildcard to help return all items with a similar structure in the table. I would also use the "ORDER BY" and sort by the Path.
While I have been working for Businesses that are Vendor partners with HP, IBM and Microsoft, my opinions and advice is my own.
The solutions provided are either sourced from my own scripting libraries or from a quick Google Search.