Reply by KnickKnack

A pair of names I always liked when we used them for a pair of gerbils we inherited a long time ago was…

”The one on the left” – which can be shortened to “left”, or “leftie”
and
”The one on the right” – which can be shortened to “right”, or “rightie”

Don’t be fooled into thinking we didn’t know exactly which one was which, regardless of whether the one on the right was actually on the left or vice versa.

-- "Do not speak – unless it improves on silence."