Do you think this was right? (see details)?

So, my grandma is the director of a home health agency, and she hired my uncle's fianc�e (the uncle is my grandma's son) fresh out of college to be the office coordinator to help her get started (she was offered higher pay than she would have gotten elsewhere, and received full benefits.) my grandma has told me countless times about how her staff doesn't do their work like they should, they make lots of mistakes, they don't meet deadlines a lot, etc. my uncle's fianc�e was no exception. my grandma has stay way after everyone else does to finish her work (sometimes even to midnight, while everyone else leaves around 5) because her staff is always bombarding her with questions while she is there (i have seen this firsthand when i went with her to work the other week) so she never has time to do her own work because she is always having to help others. she calls me all the time telling me how stressful her job is. so, the other day she got fed up with her staff not doing their work and i guess yelled at them or something because she was so frustrated with everything (i wasn't there when this happened so i don't know exactly what happened, but my dad told me about it.) my uncle fianc�e complained about it to the Human Resources department and now my grandma has to put in her 30 day notice or be fired. this makes me really mad and i find it very wrong, especially since my uncle fianc�e wouldn't even have that job if it weren't for my grandma ("don't bite the hand that feeds you") and i think my grandma had every right to be angry because THE STAFF DO NOT DO THEIR WORK LIKE THEY SHOULD!! so i am wondering, what is everyone's opinion on this situation? note: i want to hear everyone's honest opinion. btw sorry if this is really long!