You may well recognise the image above from your Facebook newsfeed or Reddit account. It is a meme which has been shared so often that it is now the very first image that comes up when you Google 'mood swing.'
But the picture's popularity is not the result of a clever marketing campaign, in fact when mum Julia Fierro first shared the photo of her daughter on Facebook, she had no intention of it being seen by anyone other than her friends.
Julia only discovered the photo had gone viral during a weekend away with her husband and their two children, aged two and five.
A friend sent her a message on Facebook with the photo of her daughter in a swing, along with the message 'Isn't this your daughter?''
What caught Julia's eye was the caption at the top of the photo, which read in big block letters - 'MOOD SWING'.
Her friend told Julia that she had found the picture on the meme site Cheezburger.com.
"'I had no idea what he was talking about," says Julia. "So I Googled 'meme' and, according to (online dictionary) Merriam-Webster, a meme is 'an idea, behavior, style, or usage that spreads from person to person within a culture.'"
In an attempt to prevent the photo being shared further, Julia emailed Cheezburger.com, asking that the photo be taken down and deleted anyone she didn't actually know from her Facebook friends list.
She thought that would be the end of the matter, but she didn't realise that the photo had already been shared on Reddit and was quickly rising to the top of their most popular memes chart.
"Millions had already viewed and shared our daughter's pout," says Julia.
Julia's friends kept sending her links to the MOOD SWING picture on different websites, offering to contact the sites on Julia's behalf, to ask to have the image removed. But at first Julia didn't share their outrage:
"My husband and I had yet to feel worried about the situation," she says. "But our friends, especially those who were also parents to young children, and, I should add, had been adoring our daughter's sweet online personality for the past two years, were offended by what they saw as the violation of our privacy, plus the creep factor of some unknown person taking possession of our baby.
If my friends were distressed, then I should be too, I told myself, feeling ashamed that I'd been so calm. How could someone steal from us like this? The nerve!
"Our friends' disapproval, plus the multiplying of our daughter's face, plus the mystery of the photo thief, began to build like an approaching storm, until it was all we spoke of. The photo. The photo.
"I blamed myself. I should have known better. I knew there was no such thing as privacy online, and that each time I posted a photo of the kids, I was responsible for the results. Still, I used my fury as a shield, deflecting my guilt by focusing on what one specifically outraged mom-friend had called 'an invasion of your precious family!'"
Julia's husband posted a message on his Facebook page asking for the person who had created the meme to reveal themselves.
The next day he got a call from a male co-worker in his twenties, who sheepishly explained that he'd seen a comment posted below the original photo on Facebook which said simply 'mood swing'. He'd found the comment funny, so he Photoshopped the words across the top of the photo and posted it on Reddit.
He promised to try to have the photo taken down - but it was a promise that would prove to be impossible to keep.
"It was my first visit to Reddit," says Julia. "I'm guessing I was born at least half a decade too early to have experienced the meme explosion that is now a part of everyday humour.
"It was difficult to decode at first, the jumble of posts and subposts and comments that made up Reddit's main page. My daughter's photo was at the very top, having received hundreds of thousands of points, and hundreds of comments."
Most of the comments were harmless observations like, "That kid woke up and said 'You can't make me have fun!'"
But Julia admits that comments like 'Her future husband is in for a good time...' and 'What a bitch,' as well as a 40-post-long debate about whether her daughter was a boy or a girl, made her feel like 'danger was lurking around every corner.'
After a couple of weeks of emailing websites asking for the photo to be taken down, Julia says she 'surrendered to the inevitability of the internet.'
"Surprisingly, once I accepted that the photo was out of my control, I felt better," she says. "Now, almost two years later, within the safety of retrospection, I even feel a bit of pride when I whip out my phone, search for "mood swing," and display a funny and adorable photo of my daughter.
It became a great story to tell - did I tell you about the time the photo of my daughter went viral?
The comedic setting of the picture, as well as the toddler's grumpy expression clearly hit a chord with people around the world - but the irony is... Julia's daughter wasn't really grumpy when the photo was taken!
"She is playing for the camera. It's an impersonation of anger," reveals Julia. "But most of the millions of people around the world who've seen the photo think she's genuinely pissed off, and I imagine this makes them love the image more, and, I imagine, makes them want to share it more, and so our daughter continues to make her way around the Internet, a cycle that repeats itself."