How to add a free item on packing slips without it appearing in the customer's cart?

Hi there,

Is there a way we can have a product show up on the packing slip but not show up in a customer’s cart? We are adding a free item for all of our retail customers and want it to show up on their packing slip so they know it is in their box but not automatically be added to their cart to avoid confusion while they are shopping.

Thank you for your help,

Meghan