This theory I really just recently made up. The "resurrection" of Daisy has made me very interested in her character, so I did what I love to do and made a theory up about her origin. Here it is:
Unlike the Mario Bros. and Peach, Daisy was not an orphan. She really didn't have the best childhood, though. Her parents passed away when she was young--like around 10 or 12--and she was sent to live with her grandparents. She lived with them for about ten years, when, due to old age, they passed on as well. Depressed, Daisy went into a deeply wooded area somewhere in the Appalachians to be alone. There, Daisy, too sad to really be watching where she's going, falls down a strange hole into an unserground cave. In the cave, there is a giant, green pipe. Thinking this is the only way back to the surface, Daisy crawls into it.
Of course, this is Warp Pipe. It leads her to Sarasaland. Confused, yet curious, Daisy explores this strange land. She eventually meets some Sarasalandians (Mushroom people, only they look Asian). They befriend her and take her to King Chai, ruler of Sarasaland and friend of Chancellor Toadstool. Daisy stays with the King a while, leading the king to think of her as the daughter he never had and her to think of him as the father she once knew. Eventually, the King asks her to stay in Sarasaland as his daughter. Daisy accepts, and she becomes Princess Daisy of Sarasaland. She soon meets Peach of the Mushroom Kingdom, and the two become fast friends.
And that's Princess Theory #2! Hope you like it. reply with your comments!