“It’s a great civil rights concern of our day.”

Former President Lyndon B. Johnson’s daughters reflected on what their father would think of gay marriage, how his legacy was tarnished by a war that broke his heart, and what it was like to honeymoon with the Secret Service in tow in an exclusive interview with Yahoo Global News Anchor Katie Couric.

Johnson’s daughters, Luci Baines Johnson and Lynda Bird Johnson Robb, took Couric around their father’s presidential library in Austin, Texas, where civil rights leaders and four living presidents will gather this week to commemorate the 50th anniversary of the landmark Civil Rights Act of 1964. Johnson pushed the bill through against the wishes of many in his own party in his first year as president.

Johnson and Robb were just teenagers when they were catapulted to the White House after JFK’s death, and remember well their father’s mission to end racial segregation in America. The sisters also suggested that they believe their father would support the spirit of what many advocates have embraced as the civil rights issue of this century: gay marriage.

Johnson said she believed LBJ would be sympathetic to the legal and political battle to force states to recognize same-sex unions if he were alive today because he was always concerned with making sure all people were treated equally.

“I think my father felt very strongly that when there was bigotry anywhere, prejudice anywhere, all of us lose out,” Johnson said. “Because it's just one more expression of hate.”

For her part, Robb said she didn’t know what her father would say, because same-sex marriage was not an issue when he was in public life.

“It's hard to project what Daddy would have thought about that because that wasn't an issue that had come upon the stage at that time,” Robb said. “But I know he really wanted everybody to be able to live up to the best that God gave them.”

Both Robb and Johnson said they personally believe gay marriage should be allowed.

“I certainly think that, if God made you a homosexual, that you should have love and affection with somebody,” Robb said. “And I would not want to deny anybody that opportunity to be happy.”

“It’s a great civil rights concern of our day,” Johnson added.

“He did everything he could to try to end the war.”

LBJ pushed through a raft of social reforms and legislation—from Medicaid to the Head Start early education program to the Voting Rights Act—as part of his “Great Society” initiative, which transformed the country. But the 36th president’s legacy was tarnished by the disaster of Vietnam.

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The Johnson daughters said his inability to pull the country out of the conflict left him brokenhearted and disillusioned by the end of his presidency.

“It broke his heart, and he did everything he could to try to end the war,” Robb said.

Both women’s husbands served in Vietnam, making the war very personal to the Johnson family.

“Every morning when we woke up and many evenings when we went to bed, Lynda and I, whose husbands were serving in Vietnam, were greeted with, ‘Hey, hey, LBJ, how many boys did you kill today?’” Johnson recalled. “And the agony that my father felt was for every one of those men and women who were serving. But it was also very personal for him because both his sons-in-law were there too.”

In the end, their father sacrificed his political career to focus on ending the war, the Johnson sisters believe. “Getting us to the peace table meant more to him than his own personal career,” Johnson said. “There's no doubt it was the agony of his life.”

“Yes, they were awkward moments.”

While their father was juggling his domestic agenda and a war, the Johnson sisters were trying to be normal teenage girls. Robb had the unique and “awkward” experience of going on her honeymoon with an entire Secret Service detail in tow.

“You get up the next morning, and there your big brothers are there, saying, ‘Hmm,’” Robb recalled with a laugh. “Yes, they were awkward moments.” 

The scrutiny made romance difficult. “I was over 30, divorced, the mother of four children, before I ever went out on a date alone,” Johnson, who was 16 when her father became president, remembered with a laugh.

But the years under the agents’ watchful eyes brought them closer. “They became like family,” Johnson said of the Secret Service.

The sudden elevation of their dad’s political position also made them question who their friends were. “There was always the fear—did somebody wanna be your friend because they thought you were worthy and they cared about you, or were they wanting to be your friend because of the position that your father was in?” Johnson remembered.

The sisters said they have great empathy for all the first families they’ve seen come and go over the past 50 years.

“We do have inequality.”

The past half-century has brought a slew of social and political changes, not all of which their father would have been happy about. Fifty years after Johnson’s signature civil rights bill passed, glaring racial inequalities still exist alongside signs of great progress.

Even as the country elected its first black president, black Americans are still twice as likely to be unemployed and three times as likely to be poor as whites. While the Johnson sisters said they believe “Daddy” would be “proud” of America for looking past racial barriers and electing a black president, they say a lot remains to be done.

“We do have inequality—well, lots of places,” Robb said.

Both sisters said they believe investing in education would help level the playing field, but that there’s no silver bullet.

“I don't know how we could have expected to have enslaved a people for 100 years and then pass a law and think instantly everything was going to be made better,” Johnson said. “It takes time.”

Yahoo News Global Anchor Katie Couric sits down with Luci Baines Johnson and Lynda Bird Johnson Robb on the 50th anniversary of the Civil Rights Act.