I know.....
Pure soul destroying franchisery at its worst.
Dark times. Dark times.
At any point that you have to involve "Son of" or "Generic added kid" in a sequel to a fairly adult movie with a big following, your movie is doomed. Take note, Mr.Speilberg.
If you add the kid, going for a Short Round factor or something, at least make them funny/useful to the plot/or at least bearable and non detrimental to the good things already existing about the movies..