If your parent Item is set to "Make-to-Order" and the components (sub-assemblies) are set to "Make-to-Order" the system will allow for nesting the child on the parent's Production Order. Meaning you get one Production Order with multiple Lines.
So while your Planning Worksheet results look the same, the Ref. Order No. has changed. If either parent or child is set to "Make-to-Stock" you will see two Production Orders suggested. If both are set to "Make-to-Order" you will only see one Production Order suggested.
As mentioned before the system will cycle down through all levels of nested "Make-to-Order" sub-assemblies and add them as additional lines on the Parent Item's Production Order.
This is assuming there is a supply need. For example, you could have a "Lot-for-Lot" Reorder Policy on one of the sub-assemblies with a Order Multiple. This could mean you have enough of the Sub-Assemblies left in stock and don't need to make those Subs on the Parent Item. This might be a little weird to see as a setup choice, but a very possible situation.
