'She says that I should just be a silent owner': Coffee shop manager put in awkward customer disputes by company's owner

These siblings have been working together, but their opposing management styles have been causing friction. 

After working as a barista during their youth, u/Unfair_Baker7448 got the chance of a lifetime. Years later, they were able to open a coffee shop of their own. It's not even their full-time job, but when they feel like it, they go play barista at their coffee shop. OP writes that they enjoy getting to meet new people, drink great coffee, and have something to do during their down time. 

However, the OP's sister manages the place. This means that even though OP owns it, their sister is probably there much more than the OP is. The sister knows all the regulars, as well as the other types of customers who come in to order their drinks. Both OP and their sister know that the customer base can be a bit demanding when it comes to their coffees, and that's where OP and their sister keep disagreeing. 

Check out this wild tale below, as well as helpful advice from the commenters. Next, this customer service manager got to tell this woman that her service was cancelled, and the reason was entirely the fault of the customer.