Title: Petunia's Fourth Year

Rating: K

Summary: Petunia Evans returns for her fourth year. The Final Horcrux is destroyed, Petunia's powers grow, and there's a new member of the Black family in Slytherin. Sequel to Petunia's Third Year! A crossover of Harry Potter and Percy Jackson!

Disclaimer: I don't own any of Rowling or Riordan's characters and I'm making nothing from this.

Chapter 10: Petunia's Magical Upset

The match between Gryffindor and Slytherin took place the day after she had gotten the letter from Narcissa. Slytherin lost, which didn't sit well with Regulus. He thought the Gryffindor's had cheated. Even Severus was upset about it but Petunia took it as 'that's life' and zoned out. The only big event that was coming up would be the vacation that students took when they headed back home. Petunia was leaving, early, so that she could attend the Winter Solstice meeting and the wedding of Narcissa and that guy that she talked about.

She really wished them well.

"So are you coming to meet your father?" she asked Severus.

"No," he said.

"Why not?" she asked him.

He looked at her and said, "I'm scared of him."

"I understand that," Petunia said, "But this is the only time that you can see him."

"Maybe later," Severus said and Petunia knew that there would be no more talking to him about that.

Lessons continued on Monday and the fourth years were worried. The older students that had already left had told them about the pile of homework that the Professors piled on you before the Christmas break. There was nothing of the sort happening and even Petunia wondered if the Professors were just doing this to take them off their guard or they would wait until later. It drove one student bonkers.

"What's wrong with him?" Severus asked.

"We haven't gotten the pile of homework that we've been warned about, yet, and he went nuts."

"Are you looking forward to it?"

"No," she answered.

She sent her paper to Gringotts about Malfoy Manor, telling him to hold it. Though she doubted that many 'light' wizards would want a place like that. The week went on without the promised nightmare and one by one the fourth years started to believe that the older students had lied. Petunia really doubted that but she wasn't going to say anything.

"Glad I don't have to worry about it," Remus said.

Both he and Lily had come back from recovery and Petunia rolled her eyes. He wouldn't be saying that when his fifth year came around. There was another monster attack but, thankfully, Dumbledore took care of it. It saved her from having to change people's memories so that they didn't go and blab to people that might cause problems.

"So are you going to camp this summer?" Petunia asked Lily and Severus.

"I don't know," Severus said.

"I'm going to," Lily said, "I want to see the States."

"You'll love it," Petunia told her, "New York is great."

She smiled at her.

"Then I'll go as well," Severus stated and Petunia wondered if this had anything to do with the fact that Lily was going.

That night Petunia crawled into bed. Even without the extra work the fourth year was starting to feel nothing like the third year. She was just tired and wanted nothing more than to sleep until she was a hundred. She hadn't been feeling like herself the last couple of days and managed to hide it, even from her sister's sight. She would have to go to her brother for help, she knew it.

The next morning she still wasn't feeling well and so she headed to her brother's office instead of the hospital wing. She doubted that Madam Pomfrey would be able to treat her. She didn't know why she doubted the Matron, but she did. The walk to his office seemed to take forever but she managed to get there and to figure out the correct password. However he wasn't there and Petunia felt like cursing not mentally contacting him.

So she turned and headed for the staff room, where he might be. Half-way back down the corridor she felt a white, hot, pain hit her. She screamed and that's when things started to shake. She screamed again and the world became color.

1111111111111111111111111111111111111111111111111111111111111111111111111111

Dumbledore raced down the corridor at the first sign that the wards were telling him that something was wrong. He latched onto the cause and shadow traveled there. When he arrived he almost backed away in horror. Petunia's whole body was glowing and he knew it could only be one thing. She was having a magical upset. A couple of moments later Flitwick appeared, panting.

"What, in the name of Merlin, is going on here?" he asked.

Dumbledore didn't answer. He was working on trying to control it and keep her from destroying half the castle. He focused everything on creating a magical barrier, to hold her there, and to contain the energy. Three hours later it was contained and he started to drink down nectar so that he wouldn't pass out.

"I told you, I told you, that she's evil," Minerva said.

"Shut up about her," Dumbledore said, "This is all part of her being my sister."

"What is it?" Flitwick asked.

"A magical upset," he said, "Her powers are growing."

"Like yours did," Flitwick reasoned and he nodded.

"She will have to remain there until things die down," he said, "I will ward off this area and redirect the students to other ways to get to class. The wards will keep others from seeing it."

"Will she become as powerful as you?"

"Yes, and take my place as someone that evil will fear."

McGonagall snorted at that but Professor Slughorn was already pulling her away.

"So my sister will be in thing until it dies down," Lily said when Dumbledore told her what had happened.

"Yes," he said, "I'm sorry about this but this is all part of her growing powers. Hopefully this will be the only time this happens."

"What about the Wolfbane?" she asked.

"Batches have been made and are timed to be used at a certain time," Dumbledore said, "I can make it as well, so no worries."

She nodded and Snape said, "Will she survive this?"

"Yes, she will," Dumbledore told him.

He said nothing but Dumbledore could tell that he was worried.