Good stuff!
This is another nice sign of progress in the early days of your career - the animation seems to be improving and the background addition of the "school book-come doodle page" really seems to fit nicely with the concept.
I personally like the gags such as "My other only son" and "Yet another lazer sound", as it shows that you're thinking about the surroundings and the breaking of the fourth wall there really does give it some nice additions to the piece.
I think that breaking the resolve of Mini Castro would only make him run off to his friends, Tiny Mao, Small Gorbachev and Little Kim, which could lead to hilarity later one for this part of the series :P
Already, the characters appear to be moving better and with that in mind, this will undoubtedly translate to better, smoother animations that you can produce in later works. If you were producing this at the time of writing, I'd suggest that you zoom in and use a smaller tool, to improve the drawing style, to match the progress with the animation. Learning new tricks is difficult, but it seems that you were doing so here.
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