Obama used family members at Sunday 's swearing - in ; Will used two relatives on Monday . ' So help me God ' not a part of presidential oath , but has been said . Legal challenge cut short before 2009 inauguration .
Obama used family Bible at Sunday 's swearing-in ; Will use two others on Monday . 'So help me God ' not required part of presidential oath , but has been said . Legal challenge fell short before 2009 inauguration .