There was a family who were peasants and didn't have the time to have good hygiene. They weren't clean and were too busy to clean and provide for their son.
I offer you the medicine if you are willing to work more.
I will do anything! OUCH!!!!
A mysterious looking person called a plague doctor appeared and explained the news of multiple people dying of a disease called the black death also called the Bubonic Plague. He said that people who are dirty and unclean will also get the infection. He said that it started in Asia then it eventually came to Europe.
OH NO! I have to go tell mom and dad! We have to stay clean or else we will... Die.
Whenever a rat or a possible flea touches a human at that time they will become affected and will need treatment. If one who got affected doesn't get the right kind of treatment that person will eventually die in 1 to 4 days!
The plague doctor gives the peasant bystander a price of, more work if he cures him with a technique called bloodletting but little did the people in those times know that, that doesn't work. The rich including lords, monarchs, etc give the plague doctors money even though bloodletting doesn't work. It actually kills them faster. So eventually that poor peasant dies...
The peasants' population went down but they earned more land and money due to the loss of many. So because the fewer peasants there are, the less the lords and emperors are going to earn which is affecting the The Decline of Feudalism.
There were people who survived this incident and, those people earned more and, got to go up ranks and, will live a better life than before. So this family shown here got to go up ranks and got to have power due to the Bubonic Plague. They were able to keep this power because the people who were orginally there died and lost their power.