Neighbors said the daughter ran out of the house screaming for help.
The mother, identified as Minerva Calvada, was declared dead at the scene, and the man was airlifted to a local hospital in critical condition.
No one has been arrested.
Police said they are unsure what happened inside the house, but they said it was a very bloody scene inside the house.
A knife was recovered at the scene next to the bodies, police said, and there were no signs of a break-in at the house.
Police said the incident was a possible murder-suicide attempt. When authorities arrived, the burners on the stove were all lit, but there was no food cooking. According to one neighbor, the couple had been fighting all day.
Anyone with information is urged to call the San Bernardino Sheriff's department at (909) 387-3589.
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