The lawyer for Hollywood filmmaker Peter Rodger said that the "family believes the child was the perpetrator".
Alan Shifman said the son had Asperger's syndrome, had trouble making friends and had been receiving professional help.
Mr Shifman added that the family had contacted police about "recent posts on YouTube" by Elliot "regarding suicide and the killing of people". The family is "devastated" and co-operating with police, he said.
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At times a little fair weather cloud may bubble up - and there will be a fairly brisk southeasterly breeze - but it will still feel hot.
Analysis of data from hospitals in England showed patients were waiting longer for ambulances, treatment and admission.
She told reporters: "I don't think it's fully sunk in how really bad that could have been, I know it's not the right decision."