A Boy and His Blob/WMG
The Boy in the Wii version is the younger brother of the Boy in the NES version.
In the second world, one of the concept art-containing pictures you unlock is of the Boy and another boy, who wears the exact same clothes as him but is bigger. It looks like the original boy. Since Younger Boy had met the Blob when his older brother had gone on adventures with him, it would explain why he wasn't afraid of him in the intro and why he was so quick to befriend the Blob--he knew about Blobs already. It would also explain Level 1-1 (Level 11): It was the same level as the original game. But while his older brother and the Blob went one way, this Boy and his blob went a different way.
- Alternatively: This Boy is the original Boy's son. If the original boy was about 13-14 in 1987, he'd be about 36 now--definitely old enough to have a kid New Boy's age.