Once there was a little rei rei,
He liked to make a sound,

And if you got him going, he gladly make this sound;
meep meep here
a meep meep there
meep meep meep everywhere

And if you heard him calling, it's just his happy sound;
meep meep here
a meep meep there
meep meep meep everywhere

So that's the rei rei song, about his happy sound;

MEEP!