Moments after the author, left, met Heidi, right.

At my book launch event in Oslo, I was shocked by a life-changing revelation.

The first thing I noticed was how bleary-eyed the woman was, and what a pretty white linen tunic she wore. She clutched a copy of my book to her chest and hesitated before stepping up to the table where I was signing copies of my memoir at the Literature House in Oslo.

She was the last person in line, and the bookstore section of this iconic literary venue in my native Norway was mostly empty now, as friends and folks attending my book launch had moved on to a nearby bar. I stood and greeted her with a smile.

“Hello, thanks for coming. What’s your name?” I said and offered her my hand.

“Hi, I’m Heidi,” she said and took my hand in hers, and the next thing she said shocked me as much as it thrilled me. In fact, my life would never be the same after that encounter.

“I’m your sister...” she continued, but then quickly added, “I mean, I’m your half sister!” I can only imagine the look on my face as I exclaimed, incredulously, “What?!?”

She continued, breathless, “Your father is also my father. I was born in 1963, and at first, he denied paternity, but then it was settled in court. I have it in writing.” Then she apologised repeatedly for shocking me while at the same time I heard someone exclaim, “Oh, my God!! Oh. My. God… Wow. Just Wow!” and that someone was of course me.

The only thing I could think of doing was to give her a big hug and tell her, “It’s OK, it’s OK.”

The woman, two years older than me, has my father’s last name, but despite our father acknowledging paternity, she grew up without a father figure and was raised by her grandparents in a small town on the northwestern coast called Molde.

It was a stigma, even in Norway, to be born out of wedlock in the ’60s. That’s probably why my father married my mom when she was three months pregnant with me in 1965.

Heidi told me, “Your dad, our dad, should be glad he didn’t marry my mother. She is a difficult person.” I was impressed by her honesty.

A chaotic mix of joy, sadness, curiosity and........

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