I am sorry to hear of your problem with Odie and Sam. My name is Rebecca. I am a veterinarian and will do my best to help.
This is what is called "displaced aggression". They are upset about the cat outside, either because she is in heat, or because they see her as invading their territory and want to chase her away, but they can't get to her so the outlet to their distress is to take it out on each other.
The best cure would be to keep them from the window where they see her, but that is probably not practical! Does the outside cat have a home? If not you could borrow a live trap from your local shelter and trap her and take her there.
You can try Feliway, a pheromone spray that has a calming effect on cats. It comes as a spray or a diffuser you can plug into a wall socket in the room where they see her. You can even get pheromone collars for them to wear.
Do they have a lot of indoor toys and games to play? It called "environmental enrichment", making the indoors interesting and fun for indoor cats, who need an outlet for their natural instincts for territoriality and predation. This is a website that has lots of idea of how to make the indoors more interesting for them, so they may not care as much when she comes by:
Let me know if this is helpful and what other questions you have.