Americans today are accustomed to seeing a teenage girl living at the White House, from Sasha Obama and Malia Obama, whose future recently made headlines, to Chelsea Clinton and Barbara and Jenna Bush. But in 1964, during President Johnson's first full year in the office, it had been a while.
As LIFE pointed out in a feature about his daughter Luci Baines Johnson, the 16-year-old younger daughter of the president was the first teen girl in the White House since William Howard Taft's 17-year-old, Helen, all the way back in 1909.
Life as a teenager in the Executive Mansion was a strange mix of normalcy (homework, $5 a week in allowance, hand-me-downs from older sister Lynda) and excitement (ball gowns, speeches in the Rose Garden). Johnson told the magazine that she was hoping to stay grounded—"I am trying to keep a hold on a private life and my friends,"—but that she could already tell it would be impossible for her life not to change.
Even so, she hoped it would not go to her head—and had a sense of the responsibility in her role, something that would apply to White House kids of any decade.
"I think my greatest responsibility as the daughter of a President is to be myself," she said, "and to be my best self."