I can't see how this could be healthy for a little boy...all that additional stress put on his growing bones/muscles/ligaments can't be a good thing.
Also, aside from the physical negatives, what about the pressures of being a "spokesmodel" at eight years old? You're gonna tell me he's gonna be normal, mentally? I guess he'll develop into another "star child" like MaryKate and Ashley or Gary Coleman (how's that for a matchup?

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I don't think it's a good idea for him to be doing this and I think his parents are cashing in on this kids obvious physical abilities. On a side note...I think I'm afraid of this little kid. :Q