@mariapopova It's ironic that Marcus Aurelius's awful decision to make his terrible son Commodus his successor led to very difficult times for everyone in the Roman Empire for the next 100 years.
I guess it was nice of him to warn everyone how to deal with the consequences of his own actions.
https://en.wikipedia.org/wiki/Year_of_the_Five_Emperors?wprov=sfla1
https://en.wikipedia.org/wiki/Crisis_of_the_Third_Century?wprov=sfla1