Normally the Statute of Limitation on felonies is 4 years. However the statute only begins to run once the offense is discovered & the offender is known, so if the police have not yet solved the crime the statute would be tolled (not running). There are other considerations, such as speedy trial, due process, etc, but they only apply if and when there is a suspect.
I am sorry to hear about your loss. From a civil perspective, someone should investigate whether the apartment complex had adequate security to prevent this. (Guards, gates, lighting, fencing, etc.). In Georgia apartments must deter foreseeable criminal attacks. I've seen many cases that initially looked like a targeted crime turn into a case against the property owner for negligent security. The statute of limitations for claims against apartment complexes can be extended if someone was charged for a crime resulting from the incident. Your brother's wife and/or children (or parents if no wife and no kids) should consult an experienced negligent security lawyer.
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