My companion disappears after Tranquility Lane, Fallout 3?

I had Jericho and Dogmeat as companions entering the pod. I come out of the pod and neither of them are there. I immediately head to Vault 101 and grab Dogmeat, and then head off to Megaton to find Jericho. Not finding him, I go back to Vault 112 to see if he's there-no luck. I never really liked Jericho, so I decided just to move on with the story. When I went to Citadel however, and tried to recruit Star Paladin, she refused to join saying I had a bad companion! I need to find Jericho, if only to fire him. Do you guys have any idea where he is? As I mentioned, I already searched Moriarty's Saloon, my house, his house, and Vault 112. Thanks for all help