It will be Christmas Day for another 21 minutes here so MERRY CHRISTMAS!
I wasn't sure if I should do this chapter as it is but it was what the muse demanded. I promise it will get happier.

Grandpop

Derek was shaken awake, a cold hand on his shoulder. He opened his eyes, remembering the vivid dream he'd had, to see his grandfather. Derek shot up in bed with wide eyes.

His grandpop smiled brightly at him. "Hello, little pup."

"Pop?"

If there was anyone in his whole family that Derek had been closer to than anyone else it was his grandpop – his mother's father. Pop had been the alpha of their pack before he died when Derek was nine. Pop loved all of his grandchildren but he and Derek had always spent more time together than any of his siblings. Derek had struggled to control his shift when he'd been young and his grandpop had spent a lot of time with him helping him control his wolf. Losing his grandfather had been the single worst thing that had ever happened to him…until Paige, until Kate. He knew he couldn't reach out and touch his pop but he desperately wanted to.

His grandpop seemed to read his mind, just like he used to when Derek was a boy, and pulled Derek into a frigidly cold hug. Derek wrapped his arms around his grandfather and, though he couldn't smell it, he remembered that specific smell of wood chips and vanilla that had always clung to him.

"I missed you," Derek said, clinging a little more tightly.

"I've been keeping an eye on you, my little pup."

Derek thought about all of the terrible things he would have had to watch happen.

"I'm sorry."

He felt the icy blast of his Pop's lips pressing to his hairline like he had when Derek had been little and Derek felt like crying. He took a deep, shuddering breath and forced the instinct down.

"There isn't anything weak in crying," Pop said, pulling away.

Derek shook his head. "If I start I might never stop."

"That's one of the reasons that you need to let your guilt go, little pup," Pop said. "Kate wasn't your fault. And you have a pack standing in front of you needing your support and a man who would love you if you just forgive yourself and learn to love yourself again."

Derek nodded, looking away from his Pop's eyes.

"What do you want to see?" Pop asked, letting the conversation rest.

Derek smiled, completely sure about what he wanted to see. "I want to see our family if Paige hadn't have died."

His grandpop's eyes turned sad. "I wish you hadn't asked to see that."

"Why?"

Grandpop reached out and grabbed Derek's hand. Then they were standing in the middle of the cemetery – staring at a spread of headstones and sitting in front of one, hunched over with his shoulders shaking, was a man. Derek looked around him but this was not where his family was buried – he started walking towards the figure on the grass. He stopped when he saw the name Talia Hale but the dates were wrong – 25th December 2020. He looked at the next headstone Michael Hale, his father, with the same date of death. Derek rushed through the stones – Cora, Peter, and then a list of names he didn't recognise all with the last name Hale and the same date of birth. Then he saw Laura's name – Laura Hale, Beloved daughter, wife, mother, and sister. Derek froze – wife, mother. He looked back at the previous headstones and worked out the ages – nine, four, one, and he knew without his grandpop having to tell him that they were her children. His knees gave out on him and he dropped down into a kneel in front of the gravestone.

"I didn't want you to ask for this," Pop said, resting an ice-cold hand on his shoulder.

"What happened?"

"That's you," Pop said instead, and Derek looked up at the other man in the cemetery.

It didn't look anything like himself to Derek – the other man had scraggly grey hair, and he seemed to be smaller than Derek thought he could be. Derek forced himself up and started walking towards the other man, noting names of gravestones as he went – Isaac Lahey, Allison Argent, Scott McCall, Melissa McCall, Kira Yukimura, Vernon Boyd, Danny Māhealani-Whittemore, Jackson Whittemore-Māhealani, Sabrina, Josh and Thomas Māhealani-Whittemore…

"They flipped a coin over whose name would go first for their kids – all adopted," Pop offered.

"What happened?"

Derek stopped, staring down at one of the gravestones – Amerie Rose Stilinski-Hale, and he thought back to the vision that Laura had shown him of the little girl with the same name searching for presents under the tree. Derek wanted to stop but he kept walking, noting the name on the next gravestone – the one where the other Derek was slumped, Przemysław 'Stiles' Stilinski-Hale, and Derek couldn't stop his eyes from slipping over the other-Derek's shoulders and catching sight of the next headstone – Logan Stilinski-Hale only two years old from the dates on the headstone.

Derek turned around and looked at his grandpop. "What happened?"

"Kate."

"How?"

"She heard about this wolf pack in Beacon Hills," Pop started. "Came to town to hunt them down. She tried to seduce you when she came to town but you weren't interested because-"

"Because of Stiles."

"Because of Stiles," Pop confirmed. "She became obsessed with you, with the pack, and then she got her hooks into Peter. My beautiful son has always been a slave to his pride and belief in the fact he's the smartest in any room. Kate twisted him beautifully."

"Peter?"

"She is a parasite, Derek, she used you in your world, but here she found the member of the pack who was the most vulnerable and used him instead."

"Why didn't I die?"

"Stiles had sent you out for ice. It was Christmas day, and the whole pack was there, all of the children."

"My children?"

Pop nodded. "Yes."

"They all burned…" Derek muttered to himself, looking at the other Derek and wondering how he'd ever survived.

"Sam Stilinski had been called into work," Pop explained. "He was going to come to the house for dinner that night. But they were all dead by the time you got home. You ran into the fire trying to save them – you had to break down a wall but by then you mother was dead and you were an alpha. You dragged them from the house but they were all dead and you were-"

Pop stopped and Derek inhaled sharply when the other-Derek turned around and looked at his daughter's grave. Other-Derek's face was burned – covered in scars like Peter had been after the first fire. He was missing the hair from the side of his head, and what hair he still had was silver-white. One of the other man's eyes was permanently red while his other was the same green that Derek saw in the mirror but they were both hollow.

"He lost everyone."

"He lost everyone," Pop agreed.

"What happened to Kate?"

"He killed her, turned feral when he couldn't make Amerie, Logan, or Stiles wake. He hunted her down and ripped her apart."

"Good."

"Sam covered for him," Pop explained. "Then he hunted down everyone else who had been involved."

"He should have let them die," Derek said.

"The sheriff was worried that you'd never come back if he let you kill them. He'd lost every member of his family but you and he couldn't face losing you as well."

Derek looked around them at the gravestones – all of them separated from the rest of the cemetery and his chest ached for the number of people that the other him lost. Derek had lost five people in his fire and there were at least five times that many headstones surrounding him. He spotted someone coming towards them from the road. Derek watched the Sheriff approach and couldn't process how much the man had aged – he looked frail. The sheriff stopped next to other-Derek and rested his hand on the werewolf's shoulder.

"They convicted Harris," the Sheriff said quietly.

Other-Derek threw back his head and howled at the blue sky. The sound ripped into Derek's chest.

"Come on," the Sheriff said. "Let's go home."

Other-Derek shook his head.

"Derek, it's time to go home – come on. We'll come back tomorrow."

The sheriff helped other-Derek stand up and they left the cemetery together – other-Derek limping as he walked next to the Sheriff.

"Neither of them live past the end of the year," Pop said in a quiet voice.

Derek reached out and trailed his finger along the letters of Stiles' name.

"So, no matter what happens I end up alone with all of my pack dead?"

Pop cuffed him around the ear. "No, in every universe Kate comes after our family. Not because of you but because that is what she does. Our families are intertwined at this place and time in history."

"So, no matter what I do I can't save them?"

Pop shook his head. "It's all about little decisions, if Stiles had have gone to collect the ice he would be the person who lost everything."

Derek froze.

"I could show you that if you wanted to," Pop continued. "I could show you that man you care about broken and sitting on your grave mourning your children and plotting revenge. Would that be better?"

"No."

"Loss like this is horrific but we need to think about what comes next."

"We die, the Sheriff and I die."

"Yes, here that's what happens. But in your life," Pop reached out and wrapped his hand around Derek's wrist, taking them back to Derek's bedroom. "In this life you, Laura, and Cora survive. Peter turns Scott, and you meet Stiles that way. You save the town from Peter – you save my Peter, and you stop the alpha pack, you save Jackson, you build a new pack, and that new pack is strong enough to stop the Argents from coming back again. You gain the trust of Chris Argent. You do amazing things. And it is terrible that so many had to die, but it is not just about the terrible things that happened to your family – it's about what happens because of them."

"What happens?" Derek asked.

"Little pup, I can only show you one thing. And I didn't want to show you what we saw. We all hoped you'd ask to see something different. Anything else really."

"Like what?"

Pop smiled. "Like one of those wonderful Christmases we had when I was alive. I'm so sorry I had to show you that."

"I asked for it," Derek said quietly.

"I have to go soon," Pop said. He cupped Derek's face in his large, cold hands, and stared at him intently. "I am proud of you, I have always been proud of you, little pup."

Derek felt his eyes prickle again.

"Goodbye, Derek," Pop said, smiling softly as he faded away.

Derek wasn't surprised by the exhaustion this time but he hadn't expected how heartbroken he would be over this visit as he crawled back into bed and the darkness took him again.

TBC