Editor's note: To mark the 50th anniversary of the assassination of President Kennedy, President Johnson's younger daughter, Luci Baines Johnson, writes for the first time about how that dark day changed her life forever. Johnson is founder and limited partner of LBJ Family Wealth Advisors, Ltd. She is married to Ian Turpin and has four grown children, Lyndon, Nicole, Rebekah, and Claudia; one stepson, Stuart; and 13 grandchildren.

For my generation, Nov. 22, 1963, will also be “a date which will live in infamy.”

Over the years I’ve found that everyone who was the age of memory recalls exactly where they were and what they were doing when they found out President Kennedy had been shot. I am no exception, except my life was changed for all time and in the most personal and profound ways.

I was a 16-year-old student at National Cathedral School in Washington, D.C. I was just entering a Spanish class when a girl came in crying, “The president’s been shot!” Half a century later, her words still ring in my ears. They were impossible to digest then and remain so.

In a matter of moments the bells of the cathedral began to ring, ring, ring. Without any instruction, hundreds of girls across the campus silently rose from seats, left their classes and marched single-file towards our gym, which also served as our chapel. I marched, too. I looked up and saw two girls cutting line — something that simply wasn’t done in an all girls’ school in the 1960s. But thoughtful students were letting my best friends, Helene and Kitty, cut line so they could comfort me.

As we found our places, every student fell to her knees. The headmistress announced the unthinkable. President Kennedy and Gov. Connally had been shot. We did not know their condition. We only knew they needed our prayers. I knew Mama and Daddy were in Texas with the president. Nobody said they were alive or dead. No one even mentioned them at all. It was all so surreal. It was my first upfront and personal confrontation with violence. Like every student, President Kennedy was my president. But he was also my father’s boss and my friend. Gov. Connally was my “Uncle Johnny.” Our families had prayed together, played together, lived together. The president and governor were both so vital, young and handsome. How could this be happening?

We were dismissed. I wandered out to the courtyard in a daze. Then I saw Gene Nunn, an agent on Daddy’s Secret Service detail, approaching. Instinctively I ran the other way, as if by doing so I could avoid a truth I couldn’t bear to face.

There was no way I could outpace Gene. He caught my arm. I buried my head in his embrace and cried, “No, Gene, no,” only to hear his repeated “I’m sorry, I’m sorry.” That’s all we could say. It was all unspeakable.

Soon I caught my senses and dared to ask about my parents. Gene said they were OK and Gov. Connally was expected to live. We agreed to leave for the safety of my home and went to tell the headmistress. We never acknowledged the president’s death. It was more than we could bear.

Years later I was touring the LBJ Presidential Library here in Austin with Helene and her two children. I asked Helene if she had returned to class after we’d been dismissed. She looked at me in shock and said, “Don’t you remember, Luci? I went home with you. We huddled on the floor of the Secret Service’s car to try and shield ourselves from potential harm. I never left your side until your parents came home.” I realized then that post traumatic shock can happen to anyone who faces a dire event. It was not until Helene reminded me that I recalled her faithful presence. I guess I had just felt so terribly alone I couldn’t even feel her comforting.

We arrived at our home, “The Elms,” to what felt like an empty house but was actually a beehive of activity. I remember trying to do something useful. All I could think to do to help was wash my hair. I knew soon there would be no time for such necessary but mundane activities.

I was glued to the television. Reporters were trying to put together the facts about how America’s innocence had been stolen along with the life of our youthful president. There was no mention of the challenging election that had brought President Kennedy to Texas, which had been a big part of the news just days before.

I wanted to meet my parents when they landed at Andrews Air Force Base. The Secret Service forbade my going. It was the first of many times I had to defer to their judgment because of possible consequences too onerous to bear.

The days that followed are a black fog in my memory. They are enveloped in pain just as the White House was covered in black. I marched behind my parents to St. Matthews for the funeral and stood behind the family at the cemetery. I wept over young John’s salute, felt the agony of our nation, wanted desperately for the nightmare to go away for the Kennedys, our country and my family. It didn’t, of course, and in the days to come I had to realize it had not been a horrific dream but a dreadful deed.

My parents seemed to never sleep. Their smiles were left for hugging those who grieved. Their days were all about trying to pick up the pieces of a grieving nation’s heart and to show the world that while evil had killed our president, it couldn’t kill our country. We would do all that we could to honor President Kennedy’s dreams for America. It was the best memorial to the best of men.

Then one early morning I heard my parents arguing. I can’t remember another time — ever. Daddy was telling Mama that the decision had been made to move into the White House on Dec. 7. Mother was protesting: “Please move any other day. Any other.” As a post-war baby, I couldn’t understand Mama’s anguish about moving on Dec. 7th, the anniversary of Pearl Harbor. I can now understand how she didn’t want that day to be the one we move into the White House and into our new destiny with history.

Daddy said that the day was fixed. It was convenient for Mrs. Kennedy. It was acceptable for the Secret Service. The choice was not to be ours.

We moved Dec. 7.

That night Mother and Daddy went to dinner at the home of Walter Jenkins, his close friend on staff. It was my parents’ first breather in over two weeks. It was my first chance to be with friends. I invited Walter’s daughter Beth to spend the night with me. It was a night I will never forget.

For the first time since the assassination, I felt at liberty to smile. Looking at my new room complete with a fireplace, all of a sudden I felt the excitement of the White House’s “trappings.” I felt fancy! Thinking Beth knew enough about fireplace flues, I lit the fire. I thought wrong. Smoke soon enveloped the unfamiliar room. I inched my way to the bathroom and on to the fireplace through the fog of smoke. All I could find was a tiny juice glass to fill with water to put out the roaring flames. It did little good. Ultimately I found a trashcan and filled it to successfully drown the fire. I then climbed on my desk and wrestled to open my gigantic window to let the smoke out. But victory was short shrift: For what I saw were the glaring eyes of a White House policeman beneath me looking straight up my nightgown.

So my first night in the White House was also the night I almost became known as the girl who burned it down!

The rest of that first week, I was no longer consumed with my new “fancy” life. I was busy trying to assist the staff in getting the smoke stains off my walls.

Our first weeks in the White House were all draped in black. We lived in a house of mourning. Our voices were low. We felt we were on a stage of sadness from which there would be no reprieve. Daddy never seemed to sleep. His hours were filled with nonstop meetings with Congress, the Cabinet, members of the business community and foreign dignitaries. There seemed to be a nonstop stream of people coming as he tried to keep our country afloat. Mother was consumed with trying to get to know her new role and minister to Daddy. I was pretty much on my own to figure it all out.

Daddy was determined to take a grieving nation’s desire to make things right and fulfill the slain president’s dreams. It was the least we could do. It was an opportunity that would not pass our way again. So endless hours were spent trying to get President Kennedy’s tax bill out. Mother’s birthday, Dec. 22, ended our month of mourning. The black that had draped the White House’s official rooms came off, and Christmas came out.

I asked my parents if I could take Christmas presents to Caroline and John. It seemed the only right thing to do. And yet I knew that the only thing they really wanted was what no one could bring them. Mrs. Kennedy, a presence of endless grace, allowed me to come. She managed smiles for a teenager trying to do the right thing. But I cannot imagine her sorrow. On Christmas Eve Daddy got the tax bill as the first of many memorials to the president. I felt for the first time that I could celebrate the season. We were going to actually go home to Texas for Christmas!

Earlier that year, I had been a young woman with a brand new driver’s license and the chance to chart my own course. Now my driver’s license was only a paper giving me the right to operate a motor vehicle, but I could no longer determine where it could go.

The Secret Service became my 24-hour-a-day companion on a life now lived on a public stage. It was every teenager’s nightmare (and the answer to prayers for every teenager’s mother). My sacrifice was of little import. The Kennedy family and our nation had lost so much that I would have gladly given all that I had to bring back. I had no right for self-pity.

The days to come would bring me reward as few know — the chance to be an eyewitness to history — and the opportunity to try and serve my country too. I had not earned this privilege. It was mine by an accident of birth and an assassin’s bullet.

But in the days to come I also came to realize much of my youth had been buried that cold November, too.