First published in 2016, the following is an excerpt of Martha Peterson's book, "The Widow Spy."

(CNN) Before I left for work that balmy spring morning in McLean, Virginia, I placed my casually worded note on the kitchen counter where my kids couldn't miss it.

It was April 1997.

Tyler was 17 and Lora was 15. They had the day off from school with no plans, so I didn't have to compete with more interesting options. Who knew what made me decide to tell them on this particular day, wondering how they would react to my secret.

Maybe this wouldn't be a big deal to them, but I was apprehensive.

Friends at work warned me, if I waited too long for this true confession, my children would be angry that I had not trusted them. I always stressed to my children that their only choice was to tell the truth.

Now I had to admit that I had lied to them.

Martha Peterson in Tbilisi, Georgia in 1976, on the sidelines of her CIA mission in Soviet Russia.

Lora called me around 10 a.m., having been awakened by her voracious hunger pangs. I replied that I wanted to meet them for lunch because they had a day off for Good Friday. I sensed this aroused her curiosity because I never met them for lunch. She agreed to get Tyler up in time to arrive in McLean by noon. I assured her that Tyler knew where the Roy Rogers was.

I had been parked for fifteen minutes when Tyler wheeled his Chevy Blazer into the spot next to mine. Tumbling into my car, Lora in front and Tyler in back, they asked, "So what's up?"

Funny, after all the roles I had played in my life, I had not devised a suitable preamble for what I was about to tell them.

So I just blurted out: "I work for CIA."

Lora looked puzzled. Tyler replied quickly, which amazed me. Yet again, how knowledgeable he was: "She's a spy." We all laughed together at how absurd this sounded: Mom a spy.

I filled the unsettled silence by explaining why lying had been my only option. I worried about telling them this secret when they were younger because children don't fully understand why being exposed as a CIA officer could pose a real danger to a family living abroad.

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When we went overseas in 1992 right after the Gulf War, I had to be certain that, if their school bus were hijacked and they were confronted by terrorists, they didn't have in their brain the fact that I worked for CIA.

They could tell "the truth" as they knew it. But now, in their teens, I told them I trusted them with my secret. And besides, we were in the States with no enemy lurking at the corner to ambush their school bus.

They sensed I was uneasy admitting my lie. I looked at both of them wondering whether I had waited too long to tell them. My daughter's next question, tinged with a hint of resentment, confirmed that I probably had. "What else aren't you telling us, Mammi?" But then, I saw a faint smile bloom on her lips, almost enjoying the fact that she had caught me in a lie.

Tyler smiled too. Relieved that they weren't offended, I knew they were curious about who I really was. I decided to tell them the whole story, even though I have always found it difficult to tell, not wanting to sound like I was bragging.

Inside the CIA

We drove to CIA Headquarters (HQS) about a mile down the road where I suggested we have lunch in the cafeteria. I included the fact that we could visit the gift shop, which snagged their immediate interest in addition to the food.

As we turned into the main CIA entrance drive, seeing it through their eyes, I realized the guard house ahead appeared disappointingly unimpressive. I had registered them as official guests earlier that day.

When I came to a stop at the security gate, the guard asked for their photo IDs. Their eyes revealed their shock at this guard addressing them directly. He seriously scrutinized their IDs, leaning in close to my window to compare their faces to the photos.

Peterson, right, at a "spontaneous" U.S. Embassy party in Moscow in 1977.

He handed back their IDs along with a red government "V" badge indicating they were visitors labeled "Escort Required." They were impressed by the formality of entering CIA. To this day, they recall how awed they were at this official attention.

Heading to the large three-story covered parking garage at the rear of the compound, we passed the front of the main building. This view is often featured on the news although neither of them said they recalled it. I had probably changed channels or at least didn't point it out to them when it came on TV as the backdrop for some spy story.

My story was going to shock them, but I planned to be selective as I unrolled my past.

Walking the long sidewalk to the new HQS building, I slowly started my story by telling them about meeting their father, Steve, in Moscow in 1975 when we were both working there in the midst of the Cold War. Past the badge machines, we rode the escalator down to the ground floor while I pointed to the replica of the U-2 spy plane suspended in the four-story atrium. I told them about Gary Powers being shot down in the Soviet Union in 1960 when I was about their age.

They listened intently while they looked around at the people and the building, still amazed at where they were.

In the first floor atrium, we entered the historical collection where an actual World War II Enigma code machine, uniforms, and other espionage articles of that era were displayed. Only mildly interested in this museum, Lora and Tyler were more eager to learn what I had done. As we moved down the hall past the portraits of the former directors on the way to the front lobby of the main HQS building, I wondered how this part of my story would affect them.

Before your dad and I met...

General Donovan's impressive larger-than-life-size statue posed near the right front wall under the saying, "Ye shall know the truth, and the truth shall set you free."

I described his significance as the Chief of the OSS and revealed that I had recently received the Donovan Award for my accomplishments throughout my career. I knew I was planting seeds of curiosity with this comment.

We moved to the center of the lobby where we stood in the center of the oversized CIA medallion emblazoned with the various shades of gray marble. This place and my apparent intimacy with it amazed them.

I walked them to the other side of the lobby where granite stars are carved deeply into the wall. Standing there with my children, I read aloud the inscription above the stars: "In Honor of Those Members of the Central Intelligence Agency Who Gave Their Lives in the Service of Their Country."

We sat on the bench facing this imposing, yet silent, wall of stars.

How do you reveal to your children that you had a life long before them, before their father, and before our quiet family home in Annandale, Virginia?

Tears came to my eyes as I looked at my children who saw my welling emotion.

"I was married once before your father. His name was John Peterson. We met in college." I looked into their eyes as they stared at me, unbelieving and silent. "He was a Green Beret in Vietnam and then he joined the CIA. He was a brave, wonderful man."

Quietly I continued. "He was killed in 1972."

Martha Peterson's late husband, John, in Laos in 1972

They blinked. Tears rolled down my cheeks. I turned to the stars and whispered, "John's star is here." I moved to the wall and gently touched the star I knew was his. They followed me, Lora's small hand lovingly and gently taking mine. Tyler slipped his arm protectively around me, both sharing my newly revealed sadness.

Moments passed in silence. I pointed to John's star in the glass-framed book beneath the stars containing a mix of names and anonymous spaces for each star on the wall. After we stood together unspeaking and looking at the wall of stars, they each touched John's star, tenderly, as I had. They understood.

But I knew they would have more questions after they reflected on this new reality.

Without words, we walked back up the stairs and headed to the more current exhibit of Cold War spy paraphernalia on loan from Keith Melton, the spy gear authority and collector.

I knew this would interest them, especially my connection to the articles on display. The glass cases and wall exhibits, I explained with new animation, contained actual spy paraphernalia that Melton had collected after the fall of the Soviet Union. Among the items were miniature cameras, concealed daggers and guns, gas masks, Berlin Wall barbed wire, miniature listening devices and all kinds of concealment devices - all the cool spy gear that made spy thrillers exciting.

Tyler and Lora were eager to know whether I had used any of this and what I had done. I told them to wait until we had lunch in the cafeteria when I would tell them the rest of my story.

I thought to my self that maybe this was too much for them to absorb all in one day.

Mom a CIA spy. Mom married before. And now the Moscow story.