'I grew up knowing I was adopted. But my mum was keeping a secret.'

I'm a 42-year-old solo mum by choice, now. But I was once a lonely, confused teenage girl with (undiagnosed) ADHD, divorced parents and a brother.

By my teenage years, my mum was absolutely depleted — mentally, physically, socially and financially. And with this in mind, I want you to know that I absolutely do not begrudge her decision to withhold this secret from me.

But by sharing it, I hope it inspires your parenting.

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She was born in 1942 and is largely a product of her time. Despite this, she raised me in forward-thinking and progressive ways: I was the only girl on the all-male soccer team. She let my "internet boyfriend" from the USA stay with us for two weeks when I was 14! And she let me stay home from school for "mental health" days long before that was trendy.

When she adopted me in 1983, I was five months old. She was 41.

On professional advice, she told me I was adopted from birth. I never knew any different. It was normal to me, and I felt no shame. In fact, I felt unique. One of a kind. Special.

What I didn't know at the time was that I was on a "special list" of children with "complex backgrounds", and the complexities were vast. Some of them were revealed to me "when necessary", like when I was 13 and got caught smoking marijuana with friends. I was told: "The woman who gave birth to you had paranoid schizophrenia, likely caused by drug use. Don't take drugs."

I took the advice.

But, it opened Pandora's Box. What else didn't I know?

I searched high and low. In cupboards, on high shelves — everywhere. I'd found every Christmas present in advance for a decade!

And I asked my mum, 'What else do you know?'

Here's where it gets tricky. Because whenever I asked a question, my mum answered. Sometimes with vagaries, sometimes specifics. She never lied.

But, despite the government advice they had received at my adoption, my family had decided to keep one secret. One secret, unless I asked.

In retrospect, I'm shocked I didn't ask the question.

And this is why I want you to consider what you're waiting for your own child to ask? I would consider taking the initiative to share — before it's too late.

I say this, because instead of hearing it from my family, the biggest secret of my life was revealed to me as if it wasn't a secret at all.

I was 18. I had decided, discretely, to search for my birth mum.

I didn't have any ill-will towards my own mum, but I wanted to know my womb story, to meet my birth mother, and to close the gaps in my imagination. It had begun with the marijuana, intensified in lonely teenage moods, and escalated again when I had eczema so severe that I couldn't use my hands. Still, I didn't want to hurt my mum in the process.

This is how, in 2001, I found myself at the Department for Children's Services NSW, waiting impatiently for a box of information to be passed across the table to me.

The box contained 18 years of artefacts: Letters my birth mum had sent me, written in childish writing; art she had created for me in colouring-in books; photos of her family.

And then, underneath it all, two mini photo albums.

And a Polaroid photo.

I immediately recognised myself in the Polaroid, age 1, but not the bleach-blonde little girl sitting beside me.

"Oh and that's Emma," the social worker said. "Your sister."

Me, aged one, and Emma, my sister. Image: Supplied.

I had grown up with a mum. I felt no absence in my life of motherly love, attention or time. My mum was and remains incredible.

But I did not have a sister.

"And that's your little sister, Niki," the social worker said matter-of-factly, pointing to a different girl as I opened one of the mini-albums. She looked just like me.

I can't tell you what this did to me.

It felt like the scenes you see in movies where someone timewarps through portals into another dimension. I'm not sure I ever came back from it.

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What happened next was the subject of a DOCS investigation that stretched on for years and was ultimately never resolved. I just gave up.

DOCS were legally required to give me the box, including the contact information of my sister. I wanted to call her immediately and fill in the gaps of the past 18 years.

We had met, once, at that very office, when we were just one and three years old.

The social worker removed some of the items from my box of treasures, noting that they were "for if [my] little sister [made] contact".

And then she refused to give me my older sister's contact information.

She had it, right in front of her, on a paper file. I could see the mobile number.

But she wouldn't share it.

At 18, I was inexperienced in life. I didn't know my rights, and I was still naïve enough to always blindly do what government departments told me to do.

She told me I could write my sister a letter and that she'd post it.

I didn't trust her. Something in me told me she'd read whatever I wrote. So I wrote (in my fanciest bubble writing):

"Dear Emma

I'm your sister.

I don't trust the social worker so I'm not writing anything.

My mobile is —

Love Rachel"

Image: Supplied.

As I was leaving the office, the social worker called my sister. We could have met that afternoon, as Emma raced to get to the office before it closed.

Instead, I went to work at Domino's Pizza for my 5pm shift. At the end of my shift, I checked my phone and saw a voice mail from Emma.

Over 20 years later, she is still is the only person in the world who leaves me voice mails.

We met that night, at a wharf in the city.

I am a full-time content creator now, and my phone camera goes everywhere with me. Back then, I carried a film camera with me everywhere, ready to capture important moments.

I was fortunate to have my camera on me that night.

And again, I had my camera on the day we met our little sister, together, just six months later — we went for a horse ride together.

Image: Supplied.

We have always been family.

But the years we lost as sisters as we grew up separately cannot be replaced.

Please know that embracing your child's biological family isn't a loss — it is a blessing.

Feature image: Supplied.