Fred and George used to wake up in the others bed alone when they were young lads seeing as they were identical they never put it together that they were switching bodies, as they grew and were doing other things that wasn't next to one another they would switch and it would scare them so bad but after a few years and telling their parents never helped as they were tricksters they learned how to handle it and snap into progress the other would leave off at. It took them till they were getting into their teens when they realized how to control it and switch on purpose, Fred would switch with George so he could do the things he was bad at and Gorge would switch with Fred so he could do the things he was bad at. When they reached Hogwarts they had it perfected and would do it to prank the others around them, especially when they would have others guess who Fred was and who George was. It all changed though when Hermione met the twins and could always tell them apart even when they would change bodies, she just knew, she would start off looking at one before looking at the one they switched bodies to.
"Fred watched Hermione walk through the Great Hall and wondered to himself how she could always know which one was which, no one ever could, not even his own family could tell them apart. She sat with Harry and Fred not too far from where George and he sat. They talked among themselves while eating their dinner and he could tell she was becoming angry with his younger brother and watched as she snapped at him before walking out of the great hall. Quickly he finished his food and before he could get up and go after her he was sitting where George had been. He looked at his brother with a startled look and George starred back with an identical look, they hadn't done that on purpose, they switched back and Fred quickly left the room to find Hermione, starting in the library, remaining as quiet as he could to find her.

A while later he had made it back to the Gryffindor tower and looked in the common area but found it empty, sighing in defeat he collapsed on the couch near the fire place and waited to see if she would appear any time soon. It was eerily quiet except for a noise of someone crying in the distance. Fred found himself moving towards the source when he heard the door to the tower open and watched Ron come through with Harry on his heels. "Hey Lads where's the little bookworm of yours?" Fred asked them fixing himself before they noticed what he was doing.

"Oh sod off George I don't know where she is and stop calling her that would ya? It's starting to piss me off." Ron snapped at him, his face turning a bit red, Harry looked between the two and before other things could be said further Fred was knocked off balance as someone ran passed him from behind. All he caught was a glimpse of brown bushy hair disappearing into the girl's dormitory. They all stared at where the figure had disappeared for a few seconds before Harry ran up the stairs after her. Fred quickly recovered and went off to find George.