The other week I was visiting a local primary school and I asked the children what made them happy.
Their families, friends and pets won the day for my audience of 4-7 year-olds. They then proceeded with the task they'd been set; to devise a character for their own story that would make them smile.
As they did so, there was audible laughter and giggles throughout the school hall as they selected various colouring pencils, thought up a sentence to describe their creation, and then made a beeline to show me what they'd achieved.
As a children's author, this is something that makes me incredibly happy - knowing that I am able to pass on my love of reading and writing to others, especially children.
And whilst I'm extremely lucky to be able to do this, it also makes me wonder how often we do things for others and indeed ourselves, that really makes us happy.
On this International Day of Happiness, wouldn't it be good if we simply exchange a smile with the person we're sat next to on the bus, the train or indeed whoever we come into contact with?
Nothing more needs to be said, but it is this small act of kindness, and reaching out to others, that can make a massive difference.
We're currently faced with so much uncertainty in the world. But one thing we can be sure of is that we're all here together. A simple smile can have such a unifying quality.
I always think that you should treat others how you would want to be treated yourself, which is why I say "good morning", to the guard on the train platform, or smile at the tube worker, who might be looking a bit downcast every time I see them.
It doesn't cost me anything and truth be told - it makes me feel good too.
Projecting positivity to the next person, in such a small way can make a huge difference to not only them, but also how you view the world and everything in it.
Dwelling on negativity will only breed more negativity, whilst embracing everything in a positive way with a can do attitude, really does make things somehow easier.
It also opens you up to new opportunities, which all of a sudden seem to appear from nowhere.
And without you even realising it, the positive energy that you're feeling is reflected in everything you do and everyone you meet.
Every morning I get up at around 5am, which might sound like a crazy time to you if you're reading this, but I love to be able to have some quiet time just for me where I can map out my day ahead.
I'm incredibly lucky to be where I am, and to do what I do, but a lot of it hasn't just happened overnight. It has been more a case of hard work, taking action and embracing every opportunity or mishap in a positive way.
Being a mum and an entrepreneur means I constantly have to juggle my time and how I approach everything. But I wouldn't change it at all. And I'm incredibly grateful for everything.
To help kick start your positive thinking, here is a really simple exercise that can work wonders to turn your day around, no matter what it's been like so far:
At least three times in a day, take a moment to stop what you're doing and look around you.
What can you see that makes you happy?
It could be something as simple as the book you're reading, your surroundings, or feeling the sun on your face.
Soak in these moments, and remember them. And then smile.
As a child I used to do this all the time.
I used to love taking the time to smell freshly cut grass, feeling my feet beneath me as I ran, enjoying the time playing on my swing at home.
Such happy memories. Made all the more special because I stopped, and took the time to remember how I was feeling.
On the whole, it's second nature for children to have a naturally positive outlook on life and to appreciate their surroundings.
Let's take a leaf out of their book and make a change to how we view the world, one small step at a time, starting today, the International Day of Happiness.
Nicola J Rowley is a children's happiness author from Walton-on-Thames, UK, whose debut picture book James and the Amazing Gift is now available for download as an ebook via Amazon UK.