There is no evidence of any "huge brawl". How many "brawls" have you seen which did not include bodily damage, broken furniture, witnesses? ALL these are conveniently missing here but doesn't stop you from libeling Michael Schiavo while complaining about those "libeling" the Schindlers by exposing their financial scams.
There were witnesses -- on both sides of the family. The fight was severe enough so that one of Terri's friends invited her to spend the night. Terri declined and told her friend she would pretend to be asleep when Michael got home. Had she accepted, she might be alive and well today, who knows? He didn't get home till much later, so she almost certainly was asleep by the time he got there. And she was still healthy.
But shortly after he got home, she suddenly ended up on the floor in cardiac arrest and all but dead. That doesn't "just happen."