The following week, Petunia was sitting on the couch once more, brooding over how incredibly bright her bedroom looked after it was painted and watching a cartoon. Lily was in the kitchen, putting away the dishes. Petunia was having the worst day: her room was not a good color, it had rained despite it being summertime, Lily was hardly paying any attention to her in the past week, and now the house was incredibly quiet. Mr. and Mrs. Evans had left the two girls home alone while they went out for dinner, as it was their anniversary.
Petunia sat alone, turning down the volume of the television. But just as she did so, she heard the running water stop and the front door open. Then it closed. Petunia sat up. "Lily!" she called, and when her sister did not reply, she grabbed her jacket off of the couch and ran outside after her sister.
Lily didn't know that Petunia was following her. Lily went all the way to the park, a lone branch in her right hand, and Petunia crept silently along behind her. When they reached the park, Lily pushed straight through a big gathering of trees until she reached a clearing. And, much to Petunia's hatred and surprise, who should be there, waiting for Lily, but Severus Snape himself.
Petunia wanted to cry out to Lily, prevent her from talking to Snape, but as Lily approached Snape and sat down, it was apparent from the look in Snape's eyes that they had met here before quite often.
Petunia, however, snuck behind a tree that was resting on the banks of a tiny little river. It was different from the one by the boy's house: cleaner and not as littered, but there were still bugs swarming around it and it took all Petunia could muster to keep the bugs away. She stayed behind the tree, listening to their conversation.
And as she listened to what the Snape boy was describing to her sister, Petunia became enthralled with everything out of his mouth: a magic school, elves, even the frightening creatures called dementors that Snape said guarded the wizard jail.
She watched as Lily picked up her stick and began to wave it in the air. The Snape boy couldn't take his eyes off Lily. Lily dropped the stick and said in hushed tones, "It is real, isn't it? It's not a joke? Petunia says you're lying to me. Petunia says there isn't a Hogwarts. It is real, isn't it?"
Petunia drew in a sharp breath, hurt by Lily's doubt. And as Snape assured Lily that it all was real, Petunia became aware of just how much the boy was polluting her sister's mind. But the way the boy spoke of it, in hushed tones, almost in reverence, even made Petunia begin to think it was real.
But it isn't! she cried silently to herself, shaking her head as if to wake herself up from a terrible dream. None of it is real. And, just as she was about to leave her sister behind, her foot slipped on the still-wet leaves and both Lily and Snape looked up.
"Tuney!" Lily cried with a smile as Petunia staggered into sight. But Snape had no kind words. He jumped, hurled blurred words at her about spying and sneaking, and it was all Petunia could do to muster up enough strength to point, jeeringly, and ridicule his clothes. (Believe me, there were all sorts of things about Snape that Petunia could have made fun of, but, being so flustered and embarrassed, his shirt was the first thing she thought of.)
But Snape's expression was so livid, angry. Petunia could see the whites of his eyes as the wind started to swell around them. Lily shivered, thinking it was going to rain, but Petunia heard a loud crack and she was on the ground, a roaring pain surging through her shoulder and tears prickling the corners of her eyes.
"Petunia!" Lily shrieked, running to where she lay. But Petunia staggered up, hurt by the satisfaction in Snape's eyes, burst into tears and ran away. "Tuney!" she cried again, and then whirled on Severus. "How could you?" she shrieked.
Severus looked shocked. "I—I didn't—"
Lily's words were slurred. "Yes, yes you did, I know you did! You hurt my sister!"
"I didn't!" But Severus's words were useless. Lily sent a look of pure loathing at Severus and ran after Petunia, who had vanished from the park.
Petunia's sandaled feet thumped down the sidewalk as she tried to wipe the tears from her eyes. "Tuney! Tuney!" she could hear Lily call, but she kept running. Finally, the short little redhead caught up with her older sister and pulled her back. "Tuney, I'm so sorry—"
"I hate him!" Petunia spat, still sobbing. "I knew he was evil from the beginning! And he's probably trying to make you turn evil as well, Lily Evans! I hate him!"
Lily fell silent, hurt at Petunia's words, because even though she was angry with Severus for hurting Petunia, she knew they were still friends and not even Petunia's loathing could change that. "I'm sorry you think that, Tuney," Lily said softly.
Petunia was silent for a moment. "Don't tell me you're still planning on speaking with him, Lily?" Lily fell guiltily silent. "Oh, Lily!" Petunia exclaimed, and turned around to march home. Lily stared wistfully after her sister, and then turned and made her way back through the trees, where Severus still sat. The two sisters were never the same again.
As Petunia marched huffily home, she came to a decision: Lily needed to be protected from that Snape boy. He was dirtying up her thoughts, Petunia decided, and Lily was too mesmerized with his tales to know the difference. Lily needed Petunia to keep her away from Snape. The day the Hogwarts letter came for Lily, she thought, Petunia would make sure there was one for her, too.