Would it be alright to put a juvenile severum about the size of a half dollar in with a full size severum. I had two but one died and the male I have left seems lonely and I believe I read they do better in pairs

It is possible, sevs can be quite aggressive so if you first remove the larger specimen to a bucket and then re-arrange all the decorations so he doesn't recognize the tank as his territory(be sure to include several hidey holes and items to break up the line of sight). then first add the smaller sev. give him 10 mins to look around and familiarize himself with his surroundings then add the larger sev. I usually do this around lights out time so they will be less active for a few hours.
Good luck!

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