Sometime in Season 1 or 2. After Rebirth, at the very earliest.

(:)

"I wish Veronica was here. She'd know what to do." Shiro absent-mindedly lamented, shaking his head as he stared at his holoscreen. They had recently discovered a highly fortified, Galra-run planet, and were trying to decipher how, exactly, to surpass it. All ideas her lackluster, and always ended in failure, capture, torture, or even death. (Thanks for the last one, Pidge.)

It was currently two days after they had received the mission, and they were all seated around the dinner table, all with holopads, all with no ideas.

Shiro's statement was a simple one, but one that had Keith looking up immediately with wistfulness.

"Yeah," the emo agreed, "she knew how to wrangle herself out of any situation with no consequences. She'd be able to crack this."

"She would've been able to figure out how to bust the entire Kerberos crew out of Galra prison successfully if she was there." Shiro hummed with fake bitterness. "But she just had to stay on Earth."

"Right where she is now." Keith agreed, resting his chin on the table and spreading his arms out as far as they could ahead of him. "Not here, and certainly not helping us plot the downfall of the Galra empire."

"Are you two talking about Shiro's old communication officer?" Pidge asked, closing down her holoscreen with a groan, standing up to stretch her muscles.

"That's right. I assume Matt told you about her?" Shiro confirmed, tilting his head at her patiently.

"And Dad." Pidge stated with a grin. "He was always very impressed by her work. I mean, she invented some of the best weapons known to man, along with disguises for each of them! A rifle in an umbrella? A machine gun in a suitcase? Who comes up with this kind of stuff?! Brilliant, pure brilliance!"

"Yo." Lance waved, butting into the conversation and looking infinitely confused. "Who are you talking about?"

"Veronica McClain." Keith and Pidge responded at the same time, giving him a look like 'you idiot. You've never heard of Veronica?'

Shiro, however, was more understanding. "Your sister."

"I thought so." Lance crooned in victory, puffing up slightly in pride. "Veronica's awesome. I didn't know she knew you, though."

"Veronica 'Sharpshooter' McClain is your sister?!" Keith cried, unbelieving. "Hot dang."

"There's no way. Veronica's a genius, and you're… um, well… not?" Pidge shrugged, looking like she was trying not to be insulting but ultimately failing. "Ah, no offense."

"Ah, none taken. Veronica was always the black sheep of the family, but in a good way." Lance glanced at Keith, smirking. "Also, heck yeah, she's my sister! What about it?"

Keith didn't answer, but he sure looked red.

"Alright, Lance, to answer your previous question," Shiro said, shifting in his seat as he shut off his holoscreen with one last annoyed look at the map, "I know Veronica because she was in a team with Matt and I. She was our communication's officer."

"As previously stated." Pidge piped up, adjusting her glasses.

"Mmhmm, yeah, gotcha, except… she never told me she was in a team with Matt! Much less the Takashi Shirogane!" Lance waved his hands about, flabbergasted. "Veronica knows the dude's my hero! Why wouldn't she tell me?"

Shiro shrugged, unsure. "She didn't always talk a lot about her personal decisions. No reasons given, she just… does."

"Just like she didn't say why she didn't go on the Kerberos mission." Keith grunted, crossing his arms. "Talk about missing out on an opportunity of a lifetime."

"Oh, yeah!" Pidge snapped her fingers, "Dad mentioned something about her getting the offer! He wouldn't tell me why she rejected it, though… I didn't realize that he just didn't know."

"Pretty sure nobody knew. The only one who knew what went on in Veronica's mind was, well, Veronica."

"Woah, woah, wait." Hunk waved his arms, silencing them. "I know I'm just sitting here listening in silence, but I think I speak for both Lance and I when I ask… she had the opportunity to who-to-the-what-now?"

"She was asked to go on a Kerberos mission." Shiro repeated, starting to look distraught. "She didn't tell you?"

"No." Lance said, looking confused. "No, she didn't. It's like you said, Shiro, nobody knows Veronica's brain except- oh. Oh, wait, never mind. Nope."

"What?" Pidge inquired, leaning toward him.

"Ah, just figured out why she wouldn't go." Lance groaned, looking guilty. "It's… my fault, in a way."

"Of course it was." Keith huffed, but was reprimanded by a sharp nudge from Shiro and a pointed look.

"You see, at the time, I was only a cargo pilot. But I really wanted to be a fighter pilot. Always had, since I was just a smol boi." Lance facepalmed into the table, hissing a bit in pain. "Veronica was always waiting up for me. Always told me she wouldn't fulfill her dream - to go into deep space - until I fulfilled mine. She had the opportunity to go further then any human before her, but she passed it up, because I was still a cargo pilot…"

"Eh, well, thank you for being a failure."

Keith grunted with what might've passed for a smile in his emo-world. "Because of you, I got to do dumb stuff with her while Shiro and Matt were gone."

"What." Lance deadpanned, confused. "She hung out with you, Mullet?"

"Usually with Matt and I. We'd do all sorts of ridiculous stuff that I now regret but those two probably don't." Shiro hummed, crossing his arms thoughtfully. "We usually left Keith behind under the super vision of my best friend."

"We drunk tea in awkward silence while Shiro and the other two went to a bar and actually got drunk." Keith deadpanned, unamused.

"No, we went to a bar and had Caprisuns. Matt insisted for 'the sake of memes'." Shiro shook his head. "And then Veronica would take us out into the woods for target practice."

"That's my sister, alright." Lance beamed, proud. "She earned the nickname of 'Sharpshooter' during her first month at the Garrison. She loved a gun more then she loved anything ever. She taught me to shoot a gun before I could even walk!"

"Seeing as how she's only about eight years older then you, and kids typically don't start walking until they're one year old, I'm beginning to worry for the safety of your family." Shiro deadpanned, a little disturbed.

"It was a nerf gun."

"That's… better." Shiro relented, nodding slowly. "It's still a gun. In a sense."

"Yeah. But it's nerf. So it's cool." Lance dismissed, waving it off.

"Wait," Allura interrupted from where she and Coran were seated in silent vigil across the table. "I am confused. Did you five not know each other before becoming Paladins?"

"Yes, because that would certain explain the lack of teamwork in the past when you were all first forming Voltron." Coran agreed, fiddling with his mustache. "Or maybe it'd fail to explain it because you learned to work together too fast? I'm not entirely sure anymore."

"Ah, wait, let me try to figure this out…" Pidge squeezed her eyes shut, calculating. "Alright, so, Shiro used to be on a team with Veronica, and since apparently Keith knows Shiro, he also knew Veronica, and I'm siblings with Matt, who also knew Veronica, and Veronica is siblings with Lance, and Lance is best friends with Hunk. Hunk, Lance, and I were on a team together, and Lance may have known Keith back in the day, but Keith doesn't remember Lance, so that's odd, and Shiro was friends with Matt and Dad so I knew him, and, uh, Hunk knew Lance so that's how he knew Keith? Apparently? So basically we all knew someone who knew someone."

"Oh, that reminds me!" Shiro chirped, perking up. "Keith and Pidge also knew each other before the Blue Lion, too!"

Keith and Pidge turned on him with equally blank expressions, and it took all Shiro's self control not to facepalm.

"What." Pidge deadpanned.

"Naw." Keith echoed, shaking his head.

"No, really." Shiro assured, huffing a little in exasperation. "Keith, remember how I used to go to family dinners with Matt and Sam?"

"Uh, yeah. No duh. I was there."

"Exactly!" Shiro waved his hands around. "And since they were 'family dinners' Pidge was there, too! Because the ones hosting were her family!"

Pidge and Keith turned to each other, matching unbelieving expressions on their faces.

Shiro groaned in despair, pressing the palm of his hands into his eyes. "Oh, Veronica and Matt…" he hummed quietly, shaking his head at his team. "If only you could see how blissfully oblivious my new team is… you'd laugh."

Keith and Pidge finally seemed to recognize each other, the latter clapping her hands together. "Oh! You're Shiro's brother! Or, technically, son, I suppose, because of the adoption papers. But like, yeah! You were that emo kid!"

"Weren't you, like… that girl who had… uh… hair?" Keith awkwardly shrugged, and Pidge, obviously oblivious to his awkwardness, nodded.

Shiro just sunk deeper into missing Veronica and Matt.

"Uh-Huh, this is great and all, but this isn't helping us figure out how to invade this Galra base!" Hunk cried, waving his holoscreen about. "I'm all for time-wasting nonsense, but not while we have no time to waste!"

Lance groaned, pulling up his screen as well, perching his cheek onto his fist.

An odd idea occurred to Shiro, and he learned toward the Cuban boy slowly. "Say…Lance… do you have any plans for the invasion? They can be totally weird and make no sense, but I'm fairly certain you're the only one who hasn't come up with a plan yet."

Lance glanced up, obviously miffed that he was actually being asked about his own two-cents. "Uhhhh… the best I can think of is for us to raid the base head on, at the center or at the grand entrance or whatever. Just right splat in the middle of the excitement; that's somewhere nobody would be dumb enough to raid."

"Yeah. Including us. We're not all dumb enough to pass off as you, Lance." Keith huffed, crossing his arms.

"No, no, Lance's onto something!" Pidge started, staring at her holoscreen. "It's significantly less guarded then anywhere else. Obviously, nobody is expecting anyone to attack right there; and even if they did, they're expecting a small group of rebels; not the whole Voltron Force."

"Well, that's the plan, then." Shiro said, straightening. "Get some rest, and we'll attack tomorrow."

"Wait, hold on. Back up. How'd you know to ask Lance?" Keith blinked, confused. "He, like, never had good ideas."

"If he grew up with Veronica, and she taught him to shoot a gun, something he's really good at, she probably taught him other skills, too, that he'd also be really good at."

Lance beamed at Shiro, proud at the praise.

"Oh, right, like how to be useful." Keith deadpanned, annoyed.

Lance deflated, scowling at Keith.

"Wait, weren't Veronica's plans always so ridiculous they couldn't possibly work but then they somehow did anyway?" Pidge asked, stretching out with a yawn as she stood up.

"Bingo." Shiro grinned, snapping his fingers at Lance. "Seems like Lance also has her knack for planning."

Lance puffed up again.

Shiro had a feeling he'd be acting bigger then he actually was for a week to come. Worth it, though, if it meant they could save more innocents from the Galra.