I'm certainly no expert on cat behavior but I wonder if you're feeding him on a set schedule. If so, his agression could be because the little guy is extremely hungry. Maybe if you leave some dry food out that he can nibble on during the day he may become more secure in knowing he'll always have something to eat and won't be such a chowzilla at feeding time.
PT friends, many of you know much more about kitten behavior than I ever will. If this is a bad idea, please chime in?
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