Finding Followers During Broken Steel
If you wake up in the Citadel's infirmary (after activating Project Purity) without your follower's in sight, here's the solution: After speaking with Elder Lyons once you wake up, the only follower you may find with you is Dogmeat (if Dogmeat was with you in the first place). If you had a second follower with you that doesn't appear, exit to the Citadel courtyard, then re-enter Ring A, then Ring B and go to the infirmary. There you should find your other follower.
It is possible the follower didn't load properly, so leaving and returning may then load them correctly.
Note: I am not the only one to come across this problem. I have read reports of others having the same trouble and using the same method, so it should be a universal solution.
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