To the surprise of absolutely no one, I wasn't allowed to go anywhere outside the house unless someone was watching me.

Ma had been frantic with worry, and I don't think she appreciated it when I refused to tell her about the details of how I'd disappeared for two weeks, apart from 'I met Pa'.

What else could I say? I wasn't supposed to know that the Olympian world even existed at all, much less how to harness the shadows.

Though, to be fair, I hadn't tried that again, I'd become slightly scared of it. It was all well and fine back in the Underworld, when I'd thought that I'd only been out for a few hours at most, but coming back to find I'd been gone for two weeks?!

How long would I disappear if I tried to do it next time?

Weeks? Months? Years?

With a start, I remembered how my little brother, Nico —or rather, Book-Nico, as I'd started to refer to him— had overextended his abilities and nearly turned into a shadow himself.

I shuddered.

That could've been me.

It had only been a matter of luck that I'd shadow-travelled to the Underworld, straight to my father, who knew how to deal with this kind of stuff. But he wouldn't always be there to help me. What if I did manage to shadow-travel myself to Hitler's office? What if I fell asleep over there?

I was pretty certain the Nazis wouldn't care that I was a kid. They'd kill me anyway.

It was nearing the 1940s. World War Two era.

I couldn't afford to be careless with my powers...

…But.

(There always is a but, isn't there?)

In this case, the but pertained to the fact that I really, really needed to protect myself — because otherwise, I'd honestly go absolutely insane from fear and anxiety.

Gaea was probably the most powerful enemy I could ever have.

(So kudos to me, I guess, for pissing off the entire personification of the Earth in little less than six years of existence. That had to be some kind of record).

But I digressed.

The point was, I had to protect myself from the monsters.

I had to.

I slipped away from Bianca's cautious babysitting (twinsitting?) a few weeks later and concentrated on the shadows just like I'd done before, and thought about the place I wanted to end up this time: somewhere small, not too far — my room, perhaps?

I nodded. My room was perfect.

I charged the wall and pulled the shadows to me, vanishing in a swirl of darkness just milliseconds before my face could collide with the bricks.

I opened my eyes cautiously after I felt myself getting spat back out.

I was outside the house, in the dark backyard. I frowned, disappointed. I'd been so sure I'd end up in my intended destination, but apparently shadow-travelling was going to be a lot harder than I'd thought.

It was also going to be a very tiring process. Even now, despite having travelled a few feet at most, I felt exhausted, like I'd just run a marathon. If I'd gone any further, I was sure I would've collapsed.

I trudged back to the house, determined to try again.

—-

February 5th, 1940.

It was our tenth birthday.

"AHH!" I woke up to Bianca's face nearly pressed against mine, and yelped in surprise, scrambling out of bed. She hastily got off too, and shot me a grin.

"You're up! Come on, Ma said she's got a surprise for us!"

That piqued my interest. Ma rarely gave us surprises.

I threw on some clothes and got myself cleaned up, before running downstairs with Bianca, bursting into the kitchen like two black-headed blurs. "Ma! Ma! Ma!" Bianca cried, going over to our mother and shaking her skirt impatiently. "Callie's awake! What's the surprise?"

Ma smiled, clearly excited. "There's someone special here to see you all, children." She gestured to someone behind her, and I turned around, my eyes widening in incredulousness as I caught sight of a familiar pale face and dark clothes.

Surely it couldn't be —

"This is your father," Ma introduced, smiling. "His name is Hades."

There was a long, awkward pause.

Bianca and I exchanged glances, and it was eventually her who took the first step.

Being the more introverted twin, I didn't protest.

"Pa?" Bianca ventured uncertainly, inching forward and holding out her arms. Hades obliged, giving my twin sister a great big hug that lifted her off her feet. "Bianca," he said with a grin. "My older twin, are you not? How are you, tesoro?"

Bianca was a little guarded with her responses — a reasonable reaction, considering she'd never met Hades before. Eventually, their small, rather forced talk petered out and Hades turned to me.

"Callie." He stated, and I noticed that the strange glint in his eyes was still there, just like when I'd first met him and told him about my powers.

"Pa," I said cautiously, narrowing my eyes.

He held out his arms, and I reluctantly embraced him. He smelled like earth and — rather alarmingly — the rich, coppery tang of blood.

I was glad when he finally released me, and folded my arms, shooting a demand at him instantly. "Why are you here?"

OK, so I was introverted, but curiosity always did get the best of me.

Which, if I think about it, isn't very good, since curiosity did kill the cat.

I don't really have a cat, but I didn't want one to die just for being curious, though.

What's wrong with a little curiosity?

"Callie!" Bianca hissed, casting an apologetic glance at Ma, who looked scandalized. I blinked out of my daze and immediately continued before she could interrupt me, grasping back onto my train of thought from earlier.

"You've never showed up to see us before," I accused, ignoring my twin's attempts to get me to shush. "Why change now?" My obsidian eyes sparked, daring him to answer.

You might be wondering, 'Oh my gods, Callie, are you trying to get yourself killed?!'

OK, you raise a valid point.

But, I mean, I was his kid.

That had to garner me at least a little patience from him.

Hades just smiled. He didn't raise his hand to smite me on the spot, either, so I took it as a win.

"Still as fiery as ever, Callie," he said fondly, and I let out a muffled yelp as he ruffled my hair, not failing to notice that he lingered for longer than necessary on my streak of red hair.

What was up with that? I wondered uneasily.

Ma pursed her lips. Clearly, she was miffed that I'd been rude to Hades, but I was saved from her wrath by Nico, who tumbled into the room, clearly excited.

I smiled when I saw him.

It was impossible not to: Nico was literally the most adorable little brother I could ever have. He was so easily excitable and had been bouncing off the walls ever since he'd been born. I simply couldn't imagine the cute boy in front of me as the scary, defensive son of Hades who'd trekked through Tartarus on his own, and hoped I'd never have to.

(Not if I had my way).

He had his annoying moments, of course, all younger siblings did. I'd lost count of how many times he'd suddenly charged at me, a cardboard sword in his hands and an eyepatch on his eye, screaming, "En guarde, hooligan!"

I snorted at the memory.

By the time I'd returned to reality, Nico had already begun chatting with Hades, not even the slightest bit bothered that he hadn't seen the man for nearly eight years. Bianca and I exchanged incredulous glances over the top of his tufty head, shaking our heads simultaneously in resignation.

"Your father is here to take you all shopping," Ma told us after a while. Hades nodded as our questioning gazes suddenly swung to him. I opened my mouth to ask why the heck are you taking us shopping all of a sudden when you couldn't be bothered to show up for ten years, but one pointed look from Ma and I clicked my jaw shut, scowling.

"Come, children," Hades said, drawing my attention to him again. He gestured to the door, and I sighed before walking out with the rest of my siblings, crossing my fingers as I did so.

Hopefully, we wouldn't all end up dead by the end of the day.