How data can be consolidated in hierarchical/parent-child/Tree for

[AYCH]

In the following example, each level has its own data (stand alone). And I
want to know, how can I get aggregate (shown under Aggregate) at each level
which is equal to its own date plus the aggregated date of its immediate
children:
Levels:
Grand Parent 1000
|
Parent 1100
|
Children 1110

Data Available in Data base:

Company Name ITEM Amount
-------------------- ---------- -------------
Grand Parent:1000 Assets 100
Liabilities -100
Parent:11000 Assets 400
Liabilities -400
Child:1000 Assets 300
Liabilities -300
How to Get Following consolidated Data which is Equal to Parent
dat+immediate childs's aggregated dat based on the same formula:

Consolidated Grand Parent=Grand Parent+consolidated Parent
Consolidated Parent =Parent+child
Company Name ITEM Amount
-------------------- ---------- -------------
Grand Parent:1000 Assets 800
Liabilities -800
Parent:11000 Assets 700
Liabilities -700
Child:1000 Assets 300
Liabilities -300

Thanks in Advance,
AYCH