As Donald J. Trump enters the White House, it is still unclear what role his daughter Ivanka will play. There has always been little doubt about which of his children Mr. Trump admires the most. Ms. Trump joined her father’s company after college, and eventually came to be considered the Trump Organization’s second-most powerful person. While officially an executive vice president for development and acquisitions, she has said titles were never taken particularly seriously at the organization, which her brothers have described as a “mom and pop” operation. Ms. Trump has leveraged her position at the Trump Organization, using its payroll, information technology and human resources to establish her own separate brand, a fashion label geared to young professional women. A stylish businesswoman, and now mother, Ms. Trump was often her father’s most potent surrogate, an essential bridge to female voters on the campaign trail. But Mr. Trump’s decision to name his daughter to his transition team, raised worries about a conflict of interest. After appearing on “60 Minutes” with her family… … her jewelry company sent out an email promoting the $10k bracelet she had worn during an interview. And a photo showing Ms. Trump attending her father’s meeting with the prime minister of Japan, a country where Ms. Trump holds business interests, spiked controversy. While her father initially put his business into the hands of his children Ivanka, Eric and Donald Jr., Ms. Trump announced last week on Facebook that she would be stepping down from her role at the Trump Organization. She also said she was taking a “formal leave of absence” from all management and operative responsibilities at her fashion brand, and moving to Washington, where her husband, the real estate investor Jared Kushner, will be serving as a senior White House adviser to Mr. Trump. What her role in Washington would be, however, she didn’t address.