I have a little boy who is the best faker on earth and he cries if he falls down, if somebody takes his toy or just if somebody looks at him the wrong way and also if somebody else is crying. I look at him sternly and say with a firm, loud voice 'No crying, you are fine' or something similar. He turns it off like a light switch. At home he probably gets something like, 'oh my poor baby' but here I call him on his nonsense and don't let him get away with it.

If this is driving you crazy then don't let it continue. Be firm with the little girl and tell her it is not acceptable to use her loud voice in the house.