Bumblebee had lost so much: Jazz, Lennox, Ironhide, Epps, His brothers in arms.
But none of them hurt as much as losing Sam.
The one thing none of them could prevent, try as they might, was Sam's own brief existence compared to their nearly-forever. By human standards, he had lived a very long life—nearly a century and a half.
And then, during the shutter of an optic, Sam was gone.
Bumblebee hadn't moved from the spot where they'd watched sunsets together for over a month. He refused when somebot thought perhaps changing his alt mode might help with the grief.
It was how he and Sam had met. He'd never change it. End of story.
When he was alone, Bumblebee shut himself in his berthroom, or disappeared from all scanners. Nobot had the heart to try to pull him out of his self-imposed isolation. After all, they were hurting too.
Sam just had that effect, both on humans and on Cybertronians. He made them care when they didn't want to or think that they could.
Then one day, Bumblebee seemed to go right back to the perky self that the First Team had met in Mission City, the one the humans had come to know. The broody, broken, hurt mech that followed the loss of Sam was gone and the bright mech they had all come to care for as a brother, friend, kin, was back.
He threw himself into work, slipping in to missions whenever he could, taking the place of this mech or that, doing everything he could to stay busy and keep the spark-break at bay.
Peace, total peace for Cybertronians, was so close. The infiltration and artillery missions were few and far between now, replaced by excursions to new planets as potential homes.
But Bumblebee acted like the war was still going full tilt. More than once, he'd kept a bonded pair together and safe when one or the other would have offlined during a mission.
Times he should have been scrap, he walked away without a single dent. Times he shouldn't have gotten away, he managed to outwit the enemy and slip between their ranks to safety.
Nobot could explain the extraordinary luck that seemed to follow the mech around like a love-sick puppy.
And through it all, Bee kept smiling, playing music and sound clips that he had picked up on Earth, dancing to one tune or another, making sure everyone was a happy as possible during an intergalactic war.
Finally, Optimus Prime and Ratchet cornered the youngling and asked flat out if Bumblebee was seeking his own offlining so he could join his human best friend in whatever afterlife they could share.
Bumblebee's optics had glitched in surprise, then he smiled and shook his helm. He reached into one of his subspace pockets and pulled out a small bit of shaped metal.
It was something Sam had given him close to the end, during an evening the sunset was particularly spectacular.
Bumblebee explained that in his grief, he had forgotten it, tucked away safe with the other mementos of his best friend until one day the subspace pocket glitched and ejected its contents. The piece of metal had been on top.
Ratchet and Optimus peered at Bumblebee's trinket, a piece of lead, aluminum, and zinc shaped into an oversized human car key. There was a phrase etched up one side:
Never drive faster than your guardian angel can fly
Bumblebee's systems hummed in pleasure when he felt a familiar, tiny warm hand rest on his helm, accompanied by the softest brush of feathers.