It had been a few years now, since that fateful battle in Egypt. Sam had grown into a fine young man and their primary voice to humanity. Optimus seemed to have settled since that battle, almost as if his protoform had melded perfectly with his frame.
One thing bothered him though. Ever since that battle he could see shadows over some of the mechs and humans from time to time.
A dusty brown horse over Lennox. A tough old warhorse by Ironhide's side. A plucky draft horse by Ratchet's pede.
When he spotted the brown paint by his charge's side he always smiled.
Once in a while he'd spot his own ghost, a palomino as he'd learned, gold and fluffy and quite young if he was correct. His human thought it was great he could see them.
Sam would hush when he mentioned the nubs though.
His own ghost had little nubs by the shoulders, just little bits of fluff and what could be feather if he was ever given enough time to look.
Sam always grinned when he mentioned those.
His human never told him what they meant. Optimus smiled too, when he caught the trails of their conversation, as if there were something had eased in his spark. He knew he'd never get either of them to tell him what they meant before they were ready.
Sometimes he'd catch a glimpse of a black horse with silver mane that seemed to smile and laugh at him.
Sam wouldn't tell him about that either, he'd just laugh.
So Bee would smile and let it be.