Rose would have just been born. Her mother would have to cast her a way in a basket into the ocean. For the was not human, this baby was born through a curse. She was born a Crystal Witch, one of the most powerful creatures on all the 7 seas. Crystal Witches are natural killers. 1 Crystal Witch could take out a whole island by itself. That basket would take to near and far. Soon after 2 weeks of life. It finds land, humans find it. The birth mother would have left a note in the basket, explaning the situation. The humans knew just what to do. Took the basket with the baby girl and threw it down the hole to the underground. Asgore would be the one to find the small baby. He would take her home to Toriel. They would name her Rose. They would make the Royal scientist, WD Gaster, her God Father. She would be loved. Gaster would do many many tests on Rose, because for supposed to be murderous, she was extremely kind.