I’ve been working at a fast Food place since end of December. My mil decided to put in her 2 weeks notice and I got asked to be manager. My boss told me basically they want me to take care of everything and they rarely want to be involved unless it’s just an emergency, because they run 2 other businesses. I hired a new person for morning shift. & my mil told the news to her granddaughter who also works night shift. For the longest I’ve been having a hard time getting Her to do her work which is simple, restock everything, clean, answer phones etc. Today I’m guessing she’s upset because she doesn’t want me to have authority over her. My boss asked me if would like to hire somebody new a more mature adult to work the night shifts. I just don’t want it to a grudge (which seems there’s already one). I’m kinda upset that the granddaughter decided to bring another teenager in to work some of her shifts because I want to train how I like things to be done & not half assed (which clearly was tonight.) I mean how can you train somebody else when your work isn’t 100%. I just need some advice. I want to build a hard working team not some working harder than others to pick up the others slack. The granddaughter attitude which is my niece suddenly changed and she seemed to hate me.