Rohit, 10 years old, writes about his best friend:

Sunil is my best friend. We have known each other since we were small boys and we have done many things together – we learned to ride our bicycles at the same time and we fly kites from his rooftop. We go to the same school and we are in the same section. We always try to sit together in class but usually the teacher makes us sit separately.

I will never have another friend like Sunil.

I know Rohit well and I have often heard him speak about Sunil. So I was taken aback when, one day, I was walking by Sunil’s house with Rohit’s sister, Anjali, 8, and she called to a girl playing in the driveway.

“Is that Sunil’s sister?” I asked.

“No,” she said, surprised. “That’s Sunil.”

“But . . . she’s a girl. Isn’t Sunil a boy?”

Anjali, without a pause, explained matter-of-factly: “To everyone else in the world, Sunil is a girl, and they all call her Pragya. Only Rohit knows that he is actually a boy.”

I think it was Anjali’s calm acceptance that really stunned me. Is it possible that it could ever be so simple, so easy to understand? Anjali had no discomfort, no judgment, no problem with Sunil’s self-identity. To me, what she was saying to me was Earth-shattering in its unlikeliness and a bit of a mind-bender. To her, it was a simple fact: The girl everyone knows as Pragya is actually a boy.

Most of us have never thought much, if at all, about what it might be like to be transgender, or to have a child who is. It has simply never struck us that there might be mothers who have given birth to a child, yet are not sure whether their baby is a boy or girl; or that there are children who feel, literally, trapped in a body, which, while healthy and perfect, is somehow all wrong.

Transgender is complicated. It doesn’t fit into the boxes we have grown up expecting, those boxes which assign us to preconceived identities, with rules, expectations and boundaries few children dare to cross. We have never considered that, from the moment of birth, a penis or a vagina on an baby decides that child’s fate.

I am no different from anyone else. I, too, am limited by my experience and my understanding. Like most of us, I didn’t grow up knowing that gender, like autism, occurs on a spectrum. That it has shades and variations. For me, like for most of us, gender was black or white. You were either male or female; you were the girl or you were the boy.

But it’s not so black or white. And why should it be? Every baby in utero, at its earliest stage, has an opening that eventually becomes the anus and a little, budlike structure that at six weeks after conception starts to become either the male or female sexual organs. All of us begin with no gender at all.

Sexual differentiation of the brain, however, doesn’t necessarily follow the same track as the physical one. While hormones accomplish the changes in both cases, the circumstances that determine their amounts – and results – are not clearly understood. What is clear is that gender identity doesn’t always match up with the genitals we happen to have. There is nothing sinister about this, and it’s not a left-wing plot to destroy the sanctity of marriage or the family as we know it. It’s just biology.

And it’s more common that we realise. Gender Dysphoria, in which a person feels one’s emotional and psychological identity as male or female is the opposite to one’s biological sex, is now a recognised medical condition. Accurate numbers are hard to get, as the condition is so stigmatised that many people never reveal it to anyone.

In India, at least half a million people live with gender dysphoria. When I informally questioned a group of pediatricians in Mumbai recently, all of them said they had children with the condition in their care.

And the single biggest problem for these kids is the fear of rejection. Knowing they may be shunned, bullied, ostracised and even killed prevents children from sharing their true selves. We have no way of knowing how many of them end their lives due to the misery of not fitting in and not being free to say why.

At the moment, scientists use words like “mutations” and “syndromes” to describe variations in what we think of as normal gender, but I believe the day is not far off when science will recognise gender differences as just one more aspect of the world’s typical diversity. After all, left-handedness was once seen as satanic and evil; the human race keeps evolving.

Sunil was brave enough to confide in a friend. Rohit and Anjali, in their calm acceptance of his reality, show us the way forward.

Gazal Dhaliwal was born a boy. At 12, he tried to commit suicide because he knew he was actually a girl and he simply had no idea how life could go on given such a contradiction. Luckily for the beautiful, confident woman he became, he had a supportive family and an accepting community.

As parents, we can make it better for children like Sunil by teaching our own children respect and simple human kindness. We can teach them how to just be interested in the world unfolding before them, how to welcome new experiences without judgment, how to be curious and open about the inevitable ways that people differ. When they encounter something new and confusing, help them stay calm. When they see a person who looks different, help them to see all the ways that person is the same.

Everyone is different. It’s not a fact to be accepted. It’s a truth to be celebrated and a very profound lesson.

And I learned it from an 8-year-old girl and a 10-year-old boy.