Rika Nonaka (Ruki's dub name) is three years older than her sub counterpart (she's 13 instead of 10). Her mother, meanwhile, stays the same age. This means her mother had her at age 15. Considering the fact that some 15-year-olds haven't even hit puberty yet, that's a major, intense change to make.
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#4
Suggested by
Spideyfan-0913
Some Details Were Changed Arbitrarily (Digimon Adventures 2)
Equally confusing is the fact that they combined Joe's two older brothers, Shuu and Shin, into one composite brother named Jim. While it's unlikely that American children will be confused by the concept of having more than one sibling, they probably will be confused about why Jim looks like two different people.
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#5
Suggested by
Spideyfan-0913
Violence between kids cut out...miserably (Digimon Adventures)
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#6
Suggested by
Spideyfan-0913
Violence between the protagonists cut out...miserably (Digimon Data Squad)