Studies find sexism slips into political coverage.Hillary Clinton is a presidential candidate, former first lady, twice-elected U.S. senator, ex-secretary of state – and a grandma. She is not the first candidate with some of those qualifications, including the grandparent part. When President George H.W. Bush – a former congressman, director of the CIA, ambassador and White House wingman - took office he had 12 grandchildren. While Mitt Romney was campaigning, two more grandchildren were added to his brood. Yet Bush and Romney’s roles as gramps were never headline worthy. Grandma Hillary, however, already has become part of the discourse. Sure,...