I am a CA lawyer.  For an answer to your question, look at CA Vehicle Code section 17151, which states that the owner of the vehicle is liable up to $15,000.  (Since you cannot "stack" policies, since there is insurance, there should be no exposure.)  Like many laws, there is an exception to the $15,000 limit.  If the plaintiff  can prove negligent entrustment in letting your brother use car, there is no $15,000 limitation (if your brother was an owner, then negligent entrustment may not apply).  I recommend you contact the insurance company and make sure they are protecting your family pursuant to the insurance contract.  Sorry about your loss.

Sorry to hear about your loss and I generally agree with Bob's post. However if the collision was caused by something other than your brother's negligence such as defect in the car or the roadway you should investigate that as your family might have a potential claim.

Also in dealing with the insurance carrier be aware that they have a duty if possible to resolve the claims within the available policy limits. If they do not do that then they may be responsible for any judgment in excess of the policy limits.

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