Sitting on the swing in the backyard of our home in Spokane, Washington, one spring afternoon three years ago, my six-year-old daughter Aspen asked me an innocent question: "Mommy, where's your daddy? Everybody has a daddy. Where's yours?"

It was a moment I had been dreading. I gave Aspen a quick answer: "He lives in Salem, Oregon." This was true, but the whole truth was so horrific that I had spent 15 years trying to forget it.

My father, Keith Jesperson, was in jail. He had confessed to raping and murdering eight women between 1990 and 1995, and was serving multiple life sentences at Oregon State Prison. He will never be released.

I was 15 when I found out my father was a murderer -- a serial killer, to be precise. The same doting six-foot-six dad who used to throw me over his shoulder and spin me round as I giggled and laughed with joy had strangled eight women and dumped their bodies at our favourite family vacation spots.

The media gave my father a nickname, The Happy Face Killer, because he sent letters bragging about his crimes to the press and signed them with a smiley face.

My young life fell apart the day Dad was arrested in March 1995. I felt and still feel overwhelmed with disgust that the man who had wiped away my tears and told me stories at night had also taken away the lives of so many innocent women.

Now, every night, I tuck in Aspen and reassure her that there are no such things as monsters. How could I tell her that some monsters are real?

Growing up in Yakima, Washington, I was the eldest of three children. My brother, Jason, my sister, Carrie, and I had good times with my dad. He was very charismatic and paid more attention to us than my mother, who was a bit of a homebody.

Dad was all about having fun, while my mother was more of a disciplinarian. But I always knew Dad wasn't perfect. I often felt that there were dark, negative emotions seething just beneath the surface.

My father worked as a long-haul truck driver and was away for weeks at a time. Sometimes, while he was on a long trip, he would send us postcards to tell us he was missing us kids. I remember how I used to feel so excited as I watched for my father's truck to pull into the driveway after a trip.

Jason, Carrie and I would run and jump up to greet him, begging him to grab us and swing us around. He was generous, and brought us home gifts and sweets. He often told me he was proud of me.

But there was another side to this gentle giant. When he was upset he would become very cold. He could be very cutting with his chauvinist remarks to my mother and routinely criticised her appearance and how she drove.

But he never hit her and they didn't yell at each other, so I assumed they were happy to be together.

There were other troubling signs, such as my father's routine torturing of our pets. One of my earliest memories is of him killing a kitten and acting as if it was entertainment. I cannot shake the image from my mind of my father wearing a twisted smile as he grabbed the defenceless stray kitten's neck and squeezed.

I can still hear my screams, pleading with him to leave the poor creature alone. I can still hear the kitten, too. My stomach turned with disgust as the kitten's body went limp.

Overwhelmed with fear and grief I ran to tell my mother. She was canning peaches when I pushed open the back door and ran to her side, yelling for her to come see what dad had done.

She looked appalled as she inspected the scratch marks the struggling cat had left on my father's forearms, but after a few words from my father the incident was simply over. He said I was being dramatic, but I knew what he did was wrong.

When I turned 10, my father came home from a trip and told my mother that he was leaving her for a lady he had met at a truck stop months before. Mom was devastated and she became even more withdrawn.

Quickly, she packed our family belongings and took us to live in Spokane, Washington, where her mother lived.

In 1990, just before my parents' divorce was final, my father started to visit my brother, sister and me on summer breaks.

He'd show up on our doorstep on a summer afternoon and announce that he was taking us to the Oregon coast for some family fun. We'd drive along the beautiful, scenic Columbia River and stop at Multnomah Falls for some ice cream.

It was during one of these trips, when I was 12, that Dad said to me: "I know how to kill someone and get away with it. I'd wear my biking shoes because they have no tread on the soles to leave a footprint. I'd cut the button off her jeans so it wouldn't leave a fingerprint."

I sat quietly in the passenger seat of his car, wondering why my father was sharing such odd and disturbing ideas. Under the seat was a pile of crime magazines and I convinced myself that he was just relaying an article he had read in one of them.

Years later, at my father's trial, I learned he dumped his first victim just yards away from where we were when he told me this.

Over time, I started to dread my father's visits. He was becoming moodier and was quick to turn cold on us. The last time I saw him out of prison was the Fall of 1994 when I was 15. He picked me up to take me out for breakfast with him.

As he put down his coffee cup on the table he looked at me sternly. "I have something to tell you," he said, "but you will tell the police ... "

I felt my stomach turn. My mind was racing to try and figure out why he would be afraid of me telling something to the police. Had he got into a fight and hurt someone? But then he pulled back from the brink.

"I want to tell you, but I can't," he said. I didn't push him.

Just a few months later, I came home from high school and caught a glimpse of my dad's mugshot on the TV news. Carrie, Jason and I stared open-mouthed at the screen. When you see something like that, you don't believe your eyes. My mother saw the shock on our faces and gathered us together to give us the news.

"Your dad is in jail," she said flatly. When Jason asked her what for, she answered, "For murder."

That was the end of the discussion.

I was stunned and sickened, but I needed to know what he had done. I decided to seek out the details at the local library. There, I learned that my father had picked up his first victim from a bar in Portland, five months after my parents had separated. Six other women met the same fate. All strangers, all raped and strangled.

The eighth victim was his girlfriend, Julie Winningham, and his relationship with her, combined with his letters to the local press and a confession he had sent to my uncle, led police to the truth.

While my father was on trial, I went to see him just once. He was escorted into a white-brick room, handcuffed and wearing a bright-orange jumpsuit. I could not take my eyes off his hairline, which was now visible since his thick wavy hair was shaved off.

To me this made him look like a criminal; it made it official. Inside, I was still hoping to hear him say that he was not guilty, that there had been a terrible mistake, that he would fight the charges and prove his innocence. But instead he said, "My best advice is to change your last name."

I broke into sobs. It was an admission of guilt.

To deal with the immense shame of my father's actions, I kept his identity a secret. My mother and family members would not mention his name and they refused to discuss anything about the crimes or trial. I didn't want anyone to know who my father was, for fear I would be judged, or someone would see similarities between us.

In 2000, when I met my husband Samuel, I avoided any conversations that might involve talking about my father. I would change the topic, afraid that Sam would learn who my father was and leave me because of it. But when Sam asked me to marry him, I had to disclose the shocking truth.

It was not easy to say, "My father is a serial killer" to the man I had fallen in love with, but I did it, and Sam said, "I'm glad you told me."

A huge weight had been lifted and I was comforted by his compassion. I had not realised how suffocating the secret had been.

We now have two children, Aspen and Jake. My children know that Grandpa "isn't a nice man" and lives in another state, far away. I'll tell them more as they grow older, but for now I want them to be the innocent children they are.

I am not in contact with my father. He doesn't deserve to have a relationship with me or with his grandchildren. I don't reply to his letters, but I started a journal years ago instead, which led to writing my memoir.

Writing the book has helped me to accept what has happened in my life and to realise that I never have to define myself through my father's actions.

'Shattered Silence: The Untold Story of a Serial Killer's Daughter' is out now

Weekend Magazine