Arcee modeling her holoform after Jerrica. Arcee going to all of the Holograms' shows and pining awfully when she has to go back to Cybertron and leave Jerrica behind. Jem calling her "Cherry" because she couldn't pronounce "chérie" [Arcee speaks french but Jem does not]. Having picnic dates up on hilltops so they can view the stars and Jerrica can sit smiling softly as Arcee tells her about all the planets and the constellations and star names [astronomer Arcee walk with me on this]. Jerrica making an album dedicated to her, filled with space and car metaphors, and Arcee still not getting that it's about her and everyone throwing their hands up about it
Jerrica learning that her Synergy tech exists because of cybertronian technology that was found and studied years ago and now using her earrings as a way to feel closer to Arcee. The Holograms watching as Jerrica loses a little bit of her pep and colour the closer it gets to Arcee leaving earth for the rebuilding efforts but not wanting Arcee to know about it because she feels selfish feeling this way
Going out for one last drive before they seperate, and staying out a little longer than they should, trying to make it last, trying to slow down time, keep a little pocket to themselves
But there's a little bit of Arcee left in Synergy. A message, just for Jerrica, that says: "You're my Vela"