Equally conformity is a huge part of the Japanese psyche - as stated the expectation is company then family and for gaijin the expectation is that families will NOT be present during your training.
If one of your first acts is to NOT conform by bringing the family some will view this neutrally - however some will view this with varying degrees of concern and question your suitability.
Should you strike one of the second group during your training....well in hindsight maybe a problem you created if your path to the final checkride becomes bumpy, maybe even impassable.
Lots to consider!