While taking their usual bath, the boys discuss how much Kyotaro is like an old man. The next day, when they go to school, they find themselves exhausted by climbing up the stairs... and learn that they're all becoming old men!
We need to find the cause, 
or we'll be in trouble.
علينا أن نبحث عن السّبب وإلّا وقعنا في مصيبة
Wir müssen schnell den Ursprung finden,
sonst ist es aus mit uns!
Tenemos que encontrar la causa
o tendremos problemas.
Hay que encontrar la causa
o tendremos problemas.
Il faut vite
en déterminer la cause.
Dobbiamo trovarne la causa, o saremo nei guai.
Precisamos encontrar a causa,
ou teremos problemas.
Надо найти корень зла,
или нам придёт конец.