[Marc Summers]

Oh I found a translation:

Toilet training with pants
Vroom vroom..
I need to go.
You know what you have to do!
Need to go! Need to go!
I need to pee!
I'm going to the toilet!
Okay! Let's do it!
I need to pee!
Alright, sit on me!
Let's do it! Let's do our best!
When you need to pee
Pee-pa pa, Pee-pa pa
Pee-pa! Pee-pa!
Pee, Pee-pa pa
Yahoo!
I peed!
I did it!
Pee-kun, bye bye!
********
Yeah!
Huh? My butt feels uncomfy!
Then you know what to do!
Uncomfy! Uncomfy!
I need to poo! I'm going to the toilet!
Alright, try hard with this!
Yeah!
When you need to poo
Poo-pa pa
Poo-pa pa
Poo-pa Poo-pa
Poo Poo-pa pa
I did a poo!
You did it, Shimajiro!
*******
Poo-kun, bye bye!
Hmmn, that felt good!
Daddy, I did a poo on the toilet, didn't I?
Yeah, that's right! From now on, you can use these!
They're pan-pan-pants!
These pants are comfy!
They're pan-pan-pants!
You should wear pants too!
Is anyone in the toilet?
I'll press the button..
Which one will you do?
Poo!
I did it!
Now I press this button!
You did it!

All it's missing now is the Final Fantasy victory fanfare.