After MANY iterations and ideas ranging from Thorfin Skullsplitter to Fyoder we finally settled on something simple and appropriate. He has two large round spots on his but so he gets Spot.
Little One hissed and growled for two days, but yesterday seemed in a better mood. They will charge each other, then stop and look around like they're not sure what to do. Well, Spot knows what to do. He wants to PLAY. He will stalk little one and try to bat her on the head. Spot is a little skittish and has deemed the underside of the bed as his "Safe Zone" but is very curious and once snagged, is happy to sit in your lap and purr up a storm. He is just as quiet or more so than Little One. At first we didn't think he could speak at all but yesterday he make the slightest chirp. It's a start.
Then this morning Little one started acting way out of character. Sluggish, didn't want to go outside. She wouldn't even chase the Dot of Summoning (laser pointer).
Rossana also noted she hadn't eaten. So it was off to the vets. She had a fever but nothing else showed up in her tests. They gave her fluids subcutaneously (under the skin) which means she was handed back to us leaking a little. We're giving her antibiotics and she's resting in her tent.