Parent child relationship for replaced Sub-Assembly

Hi

I have a defective product in the IB, lets Say A. The configuration is like

A

     -B

          -C

          -D

So B is a sub-assembly and C and D are the parts under it. We see exactly like that in the OB configuration

Now I do repair and Return. During the Job process, I do a negative issue on B (Replacing the Whole sub-assembly) and issue another B. Please note B is non-serialized.

At the end of the shipment, I see the configuration as

A

     -E

I was expecting to see the Child instances of E also, because these items are IB track able and in the BOM of the sub-assembly.But I don't see those.