For the purpose of this story, Natalie and Harry Potter are sixteen years old, and in their sixth year at Hogwarts. So, I know Snape is pretty out of character towards Natalie Potter in this story, but I was trying to think about how he'd behave, if Lily Potter had had a daughter who looked like her, and if he'd be nice to her. I do not own anything but the idea for this story and the character of Natalie Potter.
Third Person POV:
"Miss Potter, what are you doing in the library at this hour?" Natalie's head snapped up at her favorite professor's voice, and she glanced back down, embarrassed.
"Sorry, Professor. I was just studying, for tomorrow." Natalie replied, blushing.
"You're going to do wonderfully tomorrow, Miss Potter. You're great at Potions, just like your Mother." Professor Snape said.
"Thank you, Professor." Natalie said, looking down at the table again.
"Oh, bugger." Professor Snape said, pulling out a chair next to Natalie and sitting down.
"Look, Natalie-what I meant to say-you are like your Mom, you look like her, and you have her astounding Potions ability-but you are most definitely not Lily. You are you, Natalie. So, don't stress too much, and get some rest." Professor Snape said.
"Thank you, Professor." Lily said, closing the book she was reading, and sliding it into her bag. Lily stood up, nodded to Professor Snape, and left the room.