Assuming that none of the family members are ordnance experts, all we really know is that what APPEAR to be grenades and what APPEAR to be pipe bombs were found.  Until and unless HPD issues a confirmation that live munitions and explosive devices were indeed recovered, these items could include inert training grenades or novelty paperweights that anybody can buy, and miscellaneous plumbing supplies that again, anybody can buy.  This is all we really "know" at this time.

By the way, most every residence in Hawaii contains components and substances that can be construed to be "bomb making materials" if one is inclined to view them as such.

Just sayin'.