This was originally written last July, on tumblr. I thought you all would like to read it.

Luke Skywalker stared down at the Forest Moon of Endor, unwilling to take his eyes away from it for a moment. He'd heard the Emperor's order, he knew what was about to happen, but he couldn't look away. Leia was down there. He wouldn't look away. He could feel the Death Star start to power up, and be tried to brace himself. He hadn't felt much from Alderaan's destruction, but this would be different.

He was trained, now. And his twin sister was down there.

Just out of the corner of his eye, he saw green light starting to gather. Oh Force.

He didn't look away. He would not turn away.

He could just hear his father's breathing and the Emperor's cackling.
The Death Star fired.

Luke staggered back, still staring at the expanding ball that had been the Moon. His knees buckled, and he collapsed as something was ripped away from his mind. He just felt someone catch him as he fell.

He struggled to keep his eyes open. He was still in the Emperor's throne room, and he was still in danger. Leia wouldn't… He gasped. "Leia," he whispered. His eyes closed, despite his best efforts. And he knew nothing else.

Darth Vader had braced himself for Endor's destruction, but there had been something that had been different from Alderaan's. This time, something Vader had never noticed seem to disappear into the Force. And then Luke collapsed. Vader caught his son, just before his head hit the metal of the floor, but couldn't figure out why the boy had collapsed like that. Vader knelt down carefully, still holding his son.

"Luke?" he asked carefully.

Luke didn't seem to have heard him, his eyes fluttering. "Leia," Luke whispered before his eyes closed and his head lolled to the side. For a moment, Vader panicked, but a quick check in the Force showed that his son was unconscious, but otherwise healthy.

Vader looked up at his Master, still in his chair. "What is wrong with him?" Sidious asked.

Vader would have sighed. "He… I am not sure, Master. He's in shock, but I don't know why."

Sidious snorted and stood up. Vader reached out and touched his son's mind. Even unconscious, the boy had impressive shields, but he was still able to slide in. Luke's mind was… remarkably jumbled. It was as if a wall had been ripped out, and the ceiling was struggling to stay up with support on only three sides.

What Vader couldn't figure out was why. What had been down there to cause such a reaction?

Sidious knelt down next to him and placed his hand on Luke's forehead. The old man's eyes narrowed. "He should not have reacted like this," Sidious finally said.

He looked down at Luke, and Vader wondered just what his Master was thinking.

"Take him to your ship, Lord Vader," he ordered. "I will order the evacuation of the Death Star, since the Rebels are not going to give up. We will return to Imperial Center, and there we will turn young Skywalker."

"Yes, Master," Vader said. He picked up the limp form of his son and carried him out of the throne room, still puzzling over his worrying collapse.

Vader watched from the bridge of the Executor as the Death Star exploded. He couldn't bring himself to be too upset. "Set a course for Imperial Center," he ordered before heading toward where he could feel his son starting to wake up.

Vader entered the quarters he had created for his son as the boy opened his eyes. For a moment, Luke stared blankly up at the ceiling before his face crumpled. Luke sat up slowly and turned to look at Vader. He didn't say anything.

"Why did you collapse, Luke?" Vader asked.

Luke twitched. "Leia," he said. "Leia is… she was…" he swallowed.

"The princess?" Vader asked, mystified. Luke should not have had such a reaction, even if he and princess were in love.

"She was my twin sister," Luke finally said. "And she was on Endor."

Vader froze. Twins? Twins? How… "Sister?" he breathed out. "You have a twin sister?"

Luke nodded. "We were separated. I don't know the whole story, but it was to keep us safe from the Emperor. And now she's gone."

Vader bowed his head. A daughter that he hadn't even known was his. He thought back to her, and her strength. Not just of the Force, but of character. His daughter. Padmé's daughter. And now she was gone, before he could make up all that he had done to her.

Luke bowed his head. "Please, Father," he said. "I would like to be alone."

Vader could certainly understand that. "You have until we reach Imperial Center," he said. "If you want to see me before then, simply reach out, and I will come to you," he said. "I…" he paused. "I am sorry, my son."

Luke didn't respond as he left.

Twins. Padmé had been carrying twins. When he'd discovered Luke, he'd thought Padmé had been right, and he'd just been imagining a little girl's presence. But now he knew.

He already missed his daughter, though he'd never known her as anything but an enemy.

Luke, though, had been her twin. They had been bound together, though neither had known it, for their entire lives, and even before. No wonder Luke had collapsed.

He should… he should inform his Master. And he would. But… later. First, he would grieve.

Luke knew he was on the edge. Loosing Leia (and Han, and Chewie) that way had left a gaping hole in his heart. He had lost part of his reason for staying in the Light.

As Vader escorted him to the throne room on Imperial Center, Luke took a relatively deep breath. He needed all his wits about him, but he still felt scattered.

No matter. He'd do Leia proud. He'd finish this, and provide a fitting end to the monster sitting at the center of this web. For Leia.

Luke stumbled back and sat down hard on the stairs, his lightsaber clattering to the ground as he dropped it. He looked just as tired as Vader felt.

The boy stared at the still form of the Emperor. Sidious was dead.

Somehow, the Emperor was dead. Luke looked down at the lightsaber Sidious had been using.

"He's gone," Luke said, sounding shocked. He'd been the one to kill the Sith Master, though. He shouldn't have been that surprised.

"He is," Vader replied. His master was dead, while he and Luke were still alive.

"I have to let…" Luke trailed off. He slumped down. "Who survived, of the Alliance attack?" he finally asked.

"Many of the ships were destroyed, of course, though I saw your friend's freighter escape, along with most of the fighters. I believe the main command ship survived, as did a number of others. And I do not know if you know, but they destroyed the Death Star."

"Good," Luke said quietly. "That's good. That's very good."

Vader couldn't quite agree, but he knew his son had friends among the Rebels. "For now, however, we must deal with the fallout from… this."

Luke closed his eyes and nodded. After a moment, he pushed himself up and stared down at Sidious's body. "For Alderaan," he said quietly. "For Endor. For Leia, and Uncle Owen, and Aunt Beru. For Biggs, and Dak. For Ben. For Han and Chewie. For all your other victims, known and unknown. May the works of your hands be scoured away by the storm and may you wander lost in the desert until your children's children wither."

Vader felt his eyes widen. That was quite a curse to lay on someone. And yet, it was appropriate.

Vader reached out and placed his hand on Luke's shoulder. "Join me, my son," he said as quietly as he could. "I will need your help to end the war."

Luke looked down at the dead man once again. He took a deep breath and his shoulders slumped. "Yes, Father," he said quietly.

Vader's hand tightened briefly on Luke's shoulder. Finally, he had his son by his side, and never again would he lose another member of his family.