A/N: I can't exactly take credit for the idea of the princess having been traveling around the world like the prince; it was in one of the adaptions I read and I just thought it was neat.
Once upon a time there was a princess who had been traveling all over the world, searching for a prince who she could love. She'd met plenty of lovely princes, but none that she could truly love. There was always something about them that was not as it should be.
So she headed home with sadness, but on the way there she got separated from her company. That evening a terrible storm came on, with thunder and lightning and the rain pouring down in torrents. She knew she could not stay outside in these conditions, so she swiftly set to seek shelter. Coming upon a city, she hurried to knock loudly upon the gate.
Rather quickly, an older gentleman opened up the gate. From his outfit, she guessed that he was the king. She was afraid she was quite the sight from the rain and wind, as the water ran down from her hair and clothes and ran down into the toes of her shoes and out again at the heels.
"Oh, dear, come in!" he said, and so she did. Just then, a well-dressed older lady and younger man who she assumed to be the queen and the prince, along with several staff.
"I–I'm sorry for disturbing you," she shivered, trying to explain. "I'm a princess far away from my kingdom, and I got separated from my company as we were traveling. Then the storm came up, and I knew I must seek shelter."
After that explanation, everybody set to work getting her changed out of her soggy clothes and warmed up. Apparently, the prince had been traveling recently as well, and they jovially talked about it for a measure while the queen and some maids prepared a bedroom. The thought passed the princess's mind that this prince could be one that she could truly love, as his company was very enjoyable.
As she walked into the bedroom, she immediately took notice of the twenty mattresses and twenty eider-down beds that she was expected to lay down on. Their height almost touched the ceiling, and there was a ladder beside them for her to climb up on. The princess was sure it was very soft, but admittedly its height and closeness to the ceiling was a bit scary. Still, determined to not insult her hosts, she carefully climbed the ladder and laid down on top of it. Afraid of falling off or hitting her head above coupled with the still raging storm, she barely slept a wink all night.
As the princess walked into the dining room for breakfast, the queen asked gently, "How did you sleep, my dear?"
Aware that she still had dark bags under her eyes, she decided to be honest in answering, "Oh, I'm afraid I slept very badly; I scarcely closed my eyes all night. But, of course, I suppose perhaps it was because of the storm."
"Oh, but did you enjoy the bed?" the queen asked another question.
The princess sighed, "If I were to be honest, I really appreciated how comfortable you wanted me to be, but I really did not need twenty mattresses and twenty eider-downs. In fact, it worried me with how high they were and on top I feared I would hit my head against the ceiling." Internally, she blamed her rude frankness on her lack of sleep.
"Oh, dear, I'm terribly sorry!" the queen exclaimed like she genuinely hadn't thought of that. "Did you feel anything hard? Like a rock?"
"No, I don't believe so," the princess was confused by the question. How could she have felt something like a rock through so much bedding anyway? And why was the queen asking that? "But then again, I was a bit preoccupied."
"Oh, I suppose you are not a real princess then," the queen stated, which just baffled the princess even more, "Or else you would have been sensitive enough to feel the pea that I placed underneath the mattresses.
"Look, I don't really know what you're talking about, and I'm really tired, but I am a 'real' princess," the princess protested, and then she pointed out, "Do you really think a pea would withstand the weight of twenty mattresses and twenty eider-downs?"
"Probably not," the prince grinned. "Shall we go check?"
They did, and sure enough, just as the princess had predicted, the pea was completely smashed until it was just a green stain on the bottom of the mattress. After that strange affair, the queen admitted that the prince had been traveling all around in search of a bride who needed to be a "real" princess. Still, she had proved to be as sensitive as a real princess with her sleeping arrangements, but not by a pea.
Over the next few days, the prince and princess grew rather close as they waited for her company to find her. When she left to return to her kingdom, they started writing letters to each other everyday. Always believing she was a real princess, the prince would eventually take her as his wife, and when they became the king and queen, they swore never to place peas in their guests' beds.