In the beginning, there was nothing. Soon there was something, the universe. Inside this newly created universe, planets were slowly forming themselves from dust clouds that had spontaneously popped into existence. Billions of years later, life developed on these planets, and soon, sentient life. On a certain planet in the universe, a race of colourful, talking equines had evolved. They had the mystical power of magic and the glorious gift of flight, some had the magnificent might of strength. At first, they didn't get along very well, splitting off into three factions. This was later resolved, but that is a different story...
Out of the three, it can never really be decided which is the best, however, after several decades the Sun birthed a Goddess that would raise it every day, as it was growing to old to move. The Moon also birthed a Goddess, one that would raise it also. These Goddesses were Celestia and Luna. They were mystical beings called Alicorns, which could harness the powers of all three of their lesser counterparts. And because of these powers, they crowned themselves princesses of the land, centuries later, there was a war between them, but that too is another story...
Years later, Equestria itself created a being that would watch over it for eternity. This being however became rebellious, using it's Alicorn powers against Equestria. Equestria tried to stop it, but all it could do was make it a hideous insect, plagued to forever be an outcast. It was driven away by everyone, Equestria used all it's force to subconsciously command everyone to drive it away.
The being dragged itself hopelessly to the top of a mountain. It had learnt it's lesson, but it was too late. It took one more action in it's feeble life and laid eggs, it imbued the two eggs that she had just managed to lay with two strong emotions that would fill Equestria with happiness and love, so the emotions were happiness and love. The being died, leaving it's offspring to fulfil their destiny.
The first one to hatch was Happiness, it was surprisingly more pony than insect. It's legs were covered in fur, not an exo-skeleton. It's wings were made of feathers. It still had fangs and webby hair though. Unfortunately, for every force there is an equal and opposite force. Birthed from the shadows of happiness came sadness. It was incredibly insect like, and a tragedy of organic life. It looked at it's reflection in a lake and sobbed itself to sleep. It was highly intelligent, unfortunately that meant it knew it was a monster. Everywhere it went it spread sadness.
Then came love, it was half-equine, half-insect. It had holes in it's legs and a crooked horn. The first thing it saw was happiness trying to cheer sadness up, forming a loving bond. The smell of love drifted in it's direction and it walked over to them. It fed upon their love, until it was chased off. It slunk off into the woods, where it ran off into the darkness, never to return for centuries. Then came hate, the shadow of love. It hated everything it saw, it hated the mountain, it hated it's siblings, it hated the shadow it was born from, it hated life. It went round despising everything and trying to spread hate everywhere it went.
And so, the equilibrium of emotion was created.
Happiness had tried it's best to cheer sadness up. Even though sadness was it's opposite, but also it's equal, it couldn't convince it to always look on the bright side of life. Happiness slunk off into the woods, some of the sadness must of come off onto it, or maybe it was just too scared of everything. It took a deep breath and held it's head up high. It could do this, it would spread happiness everywhere and...
"Who's there?" A female voice came from behind a few bushes, happiness subsequently jumped into a nearby bush and peered out. There was a small filly looking around.
It peered out "H-hello?"
The filly stared at it "What are ya doin' behind that bush, miss?"
Happiness thought. Miss, that means I am a... Her knowledge that she was born with was quickly scoured for the word. A female. She replied to the filly "I'm...I'm just scared."
"There's no need to be scared, I'm just a filly!"
Happiness came out from behind the bush, the filly looked at her in shock "Is that...A horn... AND wings? I thought only Princess Celestia and Princess Luna had both!" The filly looked closer "And why is your mane made of...cobwebs? What is that?" The filly poked Happiness's mane.
"I...My mane is made of my hair, and I don't know what my hair is made of. So where are you from little filly?" Happiness smiled.
The filly smiled back "I'm from a little camp in this wood, I like to call it Manhattan, but my Dad says it won't catch on..."
Happiness got along well with the ponies who lived at the camp. Because of her large similarities to ponies she was able to... 'interchange genes' with them. After several generations the insectoid qualities were strained out and each new baby was a complete pony. In the present day, only one descendant still has the genes of spreading and enjoying happiness wherever it went, or, rather, wherever she went. The descendent was a pink coloured pony with no differences from most other ponies. Her special talent was creating laughter, which, in turn, comes with happiness.