Reborn as a 5-Year-Old Doomsday Queen

A five-year-old girl in an ancient village knows a locust swarm is coming before anyone else does. The girl's body is being run by a grown woman from the present day, put there by something that calls itself the Disaster Escape System. Its terms are that she gets her family through the locusts, a cold wave, a plague and a famine, one after the other. If she is still alive at the end, it sends her back to her own world with a cash prize counted in billions. Nobody in the village will take orders from a child. Some of them turn against the family, and once food runs short, neighbours go after each other. She uses what she knows and the rewards the system pays out for each stage, builds a shelter for the village, and by the last disaster the survivors are following her lead. The system then offers her the way home, money included. She has lived with this family as their daughter the whole time, and she hesitates.