So, I'm playing the original Mass Effect for the first time (don't ask), and I was doing the Rogue VI mission on Luna. I decided to throw Kaidan a bone and took him and Garrus with me.
I just completed the first bunker, left, and noticed that Kaidan is no longer in my party. Or anywhere. I went back inside the bunker and he's not there either (the map only has two marks, for myself and Garrus). His name and health don't appear in the lower left. Even the equipment and squad menus on the start menu don't show him.
Is this something that's supposed to happen? Or a glitch? There was no notification (at least, not that I noticed), and it's never happened to me before, so I'm pretty confused. I googled it and found some people talking about the same thing, but there was nothing very enlightening.