I have a home in the county of Santa Clara. If I build an ADU will my property taxes go up.

My mother is disabled and needs a structure that is convenient for her. 

Some references:

1. http://www.berkeleyside.com/2017/02/08/home-truths... Here the builder says No.

2. https://www.biggerpockets.com/forums/548/topics/37... here @marissa says some conditions can be satisfied to not trigger a reassessment.