What is the parent company? Usually if a business has a "parent company" it means that the parent company is the owner of the business, and the business is a subsidiary of the parent company. But you say that your wife and her friend own their business. So what is their relationship with the "parent company," and who really owns their business?
As Opus 17 suggested, it would probably be a good idea for your wife and her friend to sit down with a lawyer who handles small businesses, to clarify the ownership of the business and create the right documents to formalize the business relationship.
