How do you prepare a statement for sub-companies separately? How the names of the sub-companies can be shown in the p[arent statements?

I have agents (parents), which are managing separate companies. I issue the invoices to the parent and the sub-company is shown in the invoice as reference. I have two problems: 1. I cannot make a separate statement for the sub-company. 2. In the parent statement the names of the sub-companies are hidden. You can see only the number of invoices and services rendered. The clients cannot understand from the statement for which sub-company was the invoices issued.