Built my first lander including a rover. Went to Minmus with Jeremiah and Catphia, and all was going fine until I realised that my design was complete disaster.
Command module (capacity of 3 kerbals) was on orbit waiting for us
Mk1 module initially carried Jeremiah, Catphia landed on the rover's seat
After all the science experiments were done, I realised my ship only had space to return 1 kerbal to the command module!!
So I had to send Catphia back to orbit, while a sad Jeremiah stayed on the rover (see picture bellow), patiently waiting for the automated return of the ship.
The mission was a success, and all kerbals returned home safely. Thankfully I had tons of additional Delta-V as the whole thing was planned for Duna. But I can only imagine Jeremiah's joyful face when the ship landed again in Minmus, a mere 300m away from him. He was saved!