A/N: This story was written at the request of Loveangel5952. I know it's not my best work, but I hope you enjoy it.
Knockout was speechless. He glanced from one spike-headed figure to the other, eventually accepting what his optics were telling him.
"…Two Sideswipes." He muttered. "There are two Sideswipes."
"Yep." Bumblebee confirmed. "Fix-it will work on figuring out what happened and reversing it. In the meantime, since you're Sideswipe's guardian, I'm putting them both in your care.
"What?! Bumblebee!" But the traitorous lieutenant had already turned and fled. Knockout looked back at the two copies of his son and sighed. "I've had nightmares about this exact thing..."
"That's what I said!" Strongarm chipped in merrily. The Sideswipes reacted less enthusiastically. One of them gave him a withering glare, while the other shrank back like a kicked puppy.
"I'm not too happy about this either, old mech." One of the Sideswipes snapped. "It's bad enough I have to deal with you—the last thing I want is a wimpy tag-along!"
The other Sideswipe—Knockout mentally dubbed him Puppy-Sideswipe—shrank further at the comment. "I'm not wimpy! I'm as much Sideswipe as you are!" Puppy-Sides gave Knockout a pleading look. "I-I'm still your son. You still love me, right? Please still love me!"
"You're not his son, I'm his son!" Angry-Sides lunged at puppy-Sides, who yelped in alarm.
"He's my dad, too!"
"Why would he want a wimp like you?!"
"Why would he want a hot-head like you?!"
"Break it up!" Knockout shouted. Neither Sideswipe listened. Well, that hasn't changed… he thought bitterly as he tried to yank them apart. "Grimlock, help me!"
Grimlock obligingly scooped up one of the Sideswipes—Angry-Sides, judging from the cursing. Puppy-Sides hid behind Knockout, clinging to his arm like a frightened sparkling. It was…surprising, to say the least. Sideswipe hadn't been this openly sensitive since he was in his first upgrade. The two bots looked exactly alike, but they most definitely weren't Sideswipe—at least not the complete Sideswipe.
"All right, executive decision." Knockout pointed to Angry-Sides. "You—you're in Dinobot detention until you can play nice." The aggressive bot sputtered in indignation, but Knockout ignored him, instead turning to his timid counterpart. "You'll stick with me while I help Fix-it figure this out."
"Come on, buddy—let's see what's happenin' by Denny's collection of old ketchup bottles!" Grimlock cheerfully carried off his struggling captive, leaving Knockout alone with Puppy-Sides. The youngling eyed Knockout with trepidation.
"So…you're not getting rid of me?" He asked, fearful. Knockout softened. This was a side of his son that he saw only rarely—the self-doubting part, the part that longed for acceptance and encouragement. That part was the reason Knockout could never stay mad at the youngling. He rubbed Puppy-Sides' helm and smiled.
"I'm never getting rid of you." Knockout said softly. "Not ever." The look of relief on the youngling's face both warmed his spark and made it ache. Did Sideswipe really think Knockout would leave him? Did he really fear abandonment that much?
Well…if he did, this was the perfect time to fix it. Normal Sideswipe would balk at being fussed over, but Puppy-Sides would probably relish it. This was a golden opportunity for some quality time. "Come on—"Knockout wrapped an arm around the youngling's shoulders and pulled him toward the scrapyard's entrance. "Let's go for a drive. It's been a while since we had a spark-to-spark talk."
Puppy-Sides beamed like he'd been offered a million credits. "Could we go to the car wash, too? I think the other Sideswipe scratched up my paint."
Grimlock sat gazing off into space, seeming oblivious to the mech on his lap. The angry Sideswipe had struggled at first, but he'd calmed down now. Actually, that wasn't the right word. He wasn't fighting anymore, apart from an occasional wriggle, but he didn't look calm. He was…stewing, as the humans said. Grimlock merely ignored him and adjusted his grip as needed.
"…Who does that geezer think he is anyway?!" Angry-Sides burst out suddenly. Grimlock tightened his grip as he tried to escape. "I'm almost an adult! He can't tell me what to do! 'Dinobot detention,' my skidplate! Why do I have to deal with this while he hangs out with that scrawny twerp?!"
"Because you keep pickin' fights." Grimlock replied sagely. Angry-Sides scowled and huffed.
"…Bet he's enjoying this." Sides muttered. He sounded bitter. "A pretty-bot who does whatever he's told—it's what he's always wanted."
"Who?" Grimlock asked, not sure which bot Sideswipe was referring to.
"Knockout!" Sides snapped. "He's always bugging me to be careful. 'Look before you leap, Sideswipe; stay out of trouble, Sideswipe; listen when I'm talking to you, Sideswipe.' Glitchbot is everything he ever wanted me to be—even fusses about his precious paint. I bet that cheap copy of me is doing everything he can to suck up, kissing up to my guardian—" Sideswipe muttered, almost too quiet to hear. "Taking my place..."
Grimlock was silent. He wasn't the sharpest nail in the box—he knew that—but he could tell there was something going on here. "Are you angry at the other you," he asked carefully, "Or at Knockout?"
"Both! They're both slaggers! Slagging glitchheads who try to control every slagging thing I do—slaggit!" Angry-Sides fumed. Yep, there was more than anger here. But what-? Oh.
"…Knockout's not replacing you." Grimlock finally said. The younger mech stiffened, but didn't respond. Grimlock continued. "You and the other Sideswipe—you're each half of one bot. You don't need to compete. And neither of you is getting replaced." With that, he pulled Angry-Sides into a hug—a caring hug, not the restraining kind he'd been giving him for the last hour. Angry-Sides grumbled and wriggled to get away, but it seemed half-hearted. Grimlock mentally high-fived himself for doing something right.