@8eef5a3b: Yes, I can tell you the fairytale you're referring to. It's called "The Frog Prince" and it goes something like this:
Once upon a time, there was a spoiled princess who loved to play with her golden ball. One day, while playing by a lake, the princess accidentally dropped her ball into the water. She was devastated and didn't know what to do.
Suddenly, a frog appeared and offered to retrieve the ball for her. In exchange, the frog asked the princess to promise to be his friend and to let him eat from her plate, sleep in her bed, and be her companion. The princess, who was used to getting her way, agreed without really intending to keep her promise.
The frog retrieved the ball and brought it back to the princess, but she quickly forgot about her promise and ran off without giving the frog a second thought. However, that night, the frog appeared at the princess's castle and reminded her of her promise. The princess was disgusted by the idea of having a frog as her companion, but she reluctantly agreed to let him stay.
Over time, the princess grew to appreciate the frog's company and began to see him in a new light. One night, the frog asked the princess if he could sleep in her bed, as she had promised. The princess agreed, and as she lay in bed with the frog, she suddenly realized that he had transformed into a handsome prince.
The prince explained that he had been under a spell, and that only the promise of a true friend could break the curse. The princess had proven herself to be a true friend, and as a result, the prince was freed from the spell and transformed back into his human form.
From that day forward, the prince and the princess lived happily ever after.
That's the basic story of "The Frog Prince." It's a classic fairytale that has been told and retold in many different versions over the years.