On August 27 sisters Cristyn, 19, and Toni Marie, 16, were killed in the high speed crash.
Their 15-year-old brother Andrew died of his injuries on Friday.
19-year-old Jason Timothy Gomez Hernandez was also killed when he was thrown from the car.
Meanwhile, a memorial fund has also been set up to help the Cordova family.
People can donate to through Bank of America account number; 03288-7044. The routing number is 121000358.
19-year-old, Rostislav Shnayder, the alleged driver of the other car faces four felony counts which carry a maximum penalty of 10 years in state prison.
Shnayder, who was being held on $1 million bail, was scheduled to be arraigned Tuesday. It wasn't immediately known whether Shnayder had retained an attorney.
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