Kristin M. Davis was interviewed last week by officials from the office of the special counsel, Robert S. Mueller III, who is looking into the Trump campaign’s links to Russian operatives. One possible line of inquiry is Ms. Davis’s longstanding connections to Roger J. Stone Jr., a veteran political consultant and Trump adviser who has himself become a central subject in the Russia probe. Known in New York tabloids as the “Manhattan Madam,” Ms. Davis is perhaps best remembered for having claimed in 2008 that she provided escorts to Eliot Spitzer, who resigned that same year as governor of New York. Mr. Spitzer has denied any ties to Ms. Davis, 43, who spent four months on Rikers Island for running her escort service. Mr. Stone said in a statement that he is the godfather of Ms. Davis’s child and that he had been her “friend and associate” for many years. Ms. Davis hired Mr. Stone in 2010 as a political strategist when she launched her own campaign for governor of New York. She later did administrative work in Mr. Stone’s office.