Sales BOM components

Hi I am new to SAP and new to Qliksense. I have to develop a qliksense report that links the Sales BOM components with its father item in the same document. The challenge is that I get documents that have multiple fathers and there is no way to link the children(Tree_Type = I on INV1) to Its Father(Tree_Type = S on INV1). I had a look at line number there is nothing that is unique to father and his children for the same invoice/document. . e.g I get a

document that is XXX with ItemCode ZZZZ and children AA,BB,CC and same

document that is XXX with ItemCode TTTT and children GG,MM,HH

Any suggestion is welcomed. Thank you . Akha