User blog comment:Strife237/EXP gets EarthBound on Virtual Console!/@comment-6576725-20130916190500/@comment-32856285-20130916204045

In translation: there will be no Mother 4 because 4 (in Japan) is associated with death itself. It's the same reason why people had been speculating that the PS4 wouldn't be called "PlayStation 4" and it's the same reason why DBZ Budokai 4 and Budokai Tenkaichi 4 weren't made.