John came strolling down the stairs and could hear Mary humming to herself in the kitchen. He quietly shuffled in, slowly taking in the sight of his gorgeous wife happily humming and baking away.

He reached her finally, hugging her from behind. "Hey Jude, huh?"

"Good morning," she said, turning to kiss him. "Yeah... Don't know why... Just popped in my head."

"Hmm..." he said, stealing another kiss on her neck before stepping away to make himself a cup of coffee. "Must be thinking of the boys."

"I suppose..." Mary paused to look out the window in front of her. Of course she was thinking of the boys... That's who she sang the song to...

But for some reason Mary couldn't put her finger on, she didn't really believe that's why the song came to her this particular morning.

Sam had been driving most of the early morning. He'd been in Sioux Falls, spending some time with Jodie and the girls, when he'd been awoken by the ping of his phone.

The alarm he managed to hook up to the bunker had been set off.

He wanted to send Aileen a text, let her know he'd driven out but would come back to meet back up with her at Jodie's. But it was still early. And he wanted to know what was waiting for him at the bunker first.

He pulled up in front of the entrance just after 6 am. But it took him another 10 minutes to get out of the car.

He hadn't been back since Charlie had called asking for his help. He and Lucky had packed up, turned out the lights, and walked away. He'd never sworn off the place completely. That would have been ridiculous. But he hadn't exactly visited either.

Time, he kept telling himself. He just needed time.

Apparently, someone else had different thoughts on the matter.

He pulled the key out of his jacket and walked to the door. Ignoring the slight tremble - key in lock - and door open. Check.

He quietly crept in, attempting to close the door just as quietly. By the time he made it to the top of the staircase, he had quelled all unnecessary thoughts and focused solely on who, or what, he was about to face.

One step.

And then...falter. He heard...humming. No - singing. Quiet, as if the person was just singing to themselves.

Mom...

He very nearly said it out loud, but a quick shake of his head had him focused again. It's just a song. Fairly popular one at that. Sure, Mary used to sing it a lot. But it obviously wasn't her in the bunker. She was gone.

Everyone was gone.

And no one visited.

He made it down the stairs and started to simultaneously continue across the floor and pull his pistol from the back of his pants, when the singing stopped.

"Would me telling you I'm a friend of Castiel keep you from shooting me?"

Pistol was out and quickly aimed at the woman curled up in a reading chair in the next room. She carefully raised her hands while adjusting her position to keep the large book she had been reading from falling off her lap.

"I'll take that as...a maybe?"

"Who are you?" Sam snapped, taking a quick look around the space. Didn't seem like anyone else was there, but he wasn't sure.

"Like I said - friend of Castiel." She lowered her hands just as hesitantly as she'd raised them. "He's getting food. Kitchen was empty. Otherwise, I'd offer you a coffee... Or tea..." No response. "There might actually be some teabags back there...now that I think about it. But I couldn't find the kettle..."

He just continued to stare at her as maliciously as he could, before finally asking "What's your name?"

"Millie." She just stared back. Not maliciously. Just...blank. Open. Leaving it to Sam.

"OK, Millie. What is an angel doing reading in a Men of Letters library?"

"Why does everyone think I'm an angel...?" This query was mostly to herself, but at the slight visual nudge of the gun still very much pointed at her, she added "I got tired of trying to sleep and decided to read."

"That wasn't exactly what I was asking."

She started to toss a very sarcastic response back, but Sam was saved the retort by the sound of the door very loudly closing. He swung around to point the pistol at the new intruder, while keeping an eye on the reader in the corner.

"Millie, please tell me you didn't wonder off and steal a car..." Cas called down as he made his way down the stairs, carefully juggling grocery bags.

"Castiel?" Sam quietly queried.

Cas stopped on the stairs to look up. "Sam!" He hurried down the rest of the stairs, dropped the bags down at the bottom, and rushed up to his old friend. But he had to stop short, as his old friend was still pointing a pistol at him. "Sam..."

"Cas?" When the other nodded, he finally dropped the pistol and gave him a quick hug. "Long time no see!" Everyone in the room could hear the false cheer ringing through the comment.

"I'm sorry Sam. Things have been...hectic up in heaven."

"Yeah...of course! Sure!" He paused in an attempt to calm the quiver he could hear in his voice. "Everything okay?"

"Yes," Cas replied reassuringly. "All is good in heaven. Jack is doing great. And Dean is...he's settling..."

That last note drifted off as the angel caught the flash of grief across Sam's eyes.

"That's...that's good." Sam nodded. "Good to hear..."

That's when the awkward silence kicked in. Ominous awkward silence. Millie didn't want to call attention to the fact that she was, indeed, still there. But she also didn't want to be there when the silence did eventually break. She quietly closed the book and set it on the floor beside the chair. And then quietly stood. And then quietly crept forward...

"Who is that?" Sam managed to casually ask.

"That's...um..."

Millie could see the conflict on Cas' face. She knew he was just going to say it. "A friend from work," she quickly blurted, hoping to cut Cas off.

The look she got from Cas told her there was no chance of that.

"A...friend from work?" Sam gave her a suspicious look before turning back to his friend. "Cas...?"

"I'm sorry," the angel said quietly. Neither Winchester knew who he was apologizing to, as he was staring at the floor. But then he raised his head to Sam. "She's your sister."

Awkward silence started creeping in again...

"I'm going...to make breakfast..." Millie quickly made her way to grab the bags Cas left at the staircase before ducking through the open door beside it. Feeling Sam's shocked and confused gaze on her the whole way.