Klonoa seems to be around 6-7 in the original, but in Klonoa 2 I think he's supposed to be 13, at least I remember reading that somewhere.
Now in the Wii remake, he acts like a very shy version of his Klonoa 1 self but looks the same age as in Klonoa 2, and add Eric Stitt's voice, it feels all over the place. It's like they were confused on how they should handle the character. No, wait, it feels more like they were confused about the whole game. Looking at the North American redesign, I get the feeling that they were contemplating completely rebooting Klonoa to be something different, more "western", but then scrapped it.
Haha, imagine how that would have looked like. Sheesh.