AR Aging by Parent Company

Hi!
I am wanting a BAQ that pulls our AR aging for ALL our companies into one line by parent customer.
The problem I am having is running this at a later date. i.e. I am running the aging in late February for January but it is excluding the invoices that had been paid within that February period.
I also cannot figure out how to combine the data between the two companies.
Any help or a BAQ Export/Import sample would be great.
Thanks!