Finally completed bryanacute's ponies, sorry its taken a while.
They are taking a rest during their climb across the rainbow into heaven. Not sure if you can make it out, but at the end of the rainbow is a doorway.
Since you said Neptune and Cleopatra acted like a king and queen, that's what I've drawn them as. Wonder had a lovely personality and he became an angel, and I figured he would watch over them in heaven