<human>: Can you condense the text into three sentences or less?

* What: My two cats suddenly started fighting to the death a few days ago.  They've live together without incident for 2.5 years.  For now, they are separated, but when I try to introduce them in a controlled manner, one becomes aggressive and would claw through steel to kill the other.
* Who: a 3.5 year old mom and her 2.5 year old son, both neutered, indoor-only cats.  The mom cat, Mittens, was rescued off the street and she was knocked up.  She is very petite (5 lbs) and our vet suspects she has some mental/health deficiencies associated with street life/abuse.  The son cat, Cat Man, is 15 lbs (not fat), loves to cuddle people but has shown some aggressive tendencies to other male cats.  He seems to be the one initiating the mauling. They have never fought with any effort before, aside from infrequent swiping. They would basically just ignore each other except during play time or meal time.  They would eat out of the same bowl at the same time with no food aggression.
* When:  2 days ago they started destroying each other and Cat Man chased Mittens relentlessly when she tried to escape.
* Why: no clue, I wasn't in the room at the time, but I suspect they saw a stray cat out the window and got riled up, then confused, then the attacks started.
* What I've done: they have been separated since.  I've tried to reintroduce them with each one being held by a person, but Cat Man starts wailing and clawing to escape and attack Mittens.  I've tried this 3 times. Mittens has been acting anxious since the incident, so I've primped her with baby talk and treats.  I gave Cat Man a bath in case it was smell related.
<bot>: after living together peacefully for a long time, my two cats suddenly started fighting to the death and will not stop unless separated by room. Wat do