Apply a direct discount on the billing plan and the changes will be visible on *all future bills of the children belonging to the respective billing plan.
Step 1: Access the list of billing plans. Go to Billing > Configuration > BIlling Plans And Select Actions > Edit
Step 2: Press the "Next" button until you reach the final page, then press "Add discount".
Step 3: In the window that appeared enter the discount value, the validity of the discount (a time frame in which the discount will be active) and a description in the field "Discount for:" eg: "Discount 10% for brother".
*Attention! If you want the discount to apply only for a certain period of time, for example, until the end of the year or until the child's brother finishes the kindergarten / school, then in the field called "Validity discount", choose the date by which this discount applies, if you do not select anything the discount will be applied automatically to all future invoices.
Apply a direct discount on an invoice (to an invoice that has not yet been issued).
Using this method the discount will be applied only on the invoice to which you applied the discount.
Step 1: In the "Parent invoices" tab under the "Invoicing" module, click on "Pending" (or "Issued" if the invoice has already been issued but is not yet paid) > "View invoice" on the invoice for which you want to apply discount.
Step 2: Next to the product you can see a gray button with the symbol "%" which is called "Discount", click on it.
Step 3: Select whether you want to apply a percentage or fixed discount, add the amount and a description and then click "Add".
Step 4: You will be able to see the discount applied to the invoice, all that remains to do is click on "Save".