Can my wife be sued also

The law in Florida basically says that the Owner of a vehicle is responsible for any negligent operation of the vehicle. From the facts that you have provided, it would appear that your wife should not be sued, or liable for injuries caused by your adult son. In Florida the doctrine is called the "Dangerous Instrumentality Doctrine." Which is followed in Florida for the reasoning that a car is a dangerous instrument, and the owner must be held responsible for any negligence in the vehicle's operation.
From the facts as I understand them only you yourself as an owner or your business, or LLC (if it was a company vehicle) and your son (who was an adult at the time of the crash) would be proper defendants. The key question is who is on the title to the vehicle? Anyone on the title to the car, and the driver will likely be named as a defendant in a suit for damages.

I hope this information is helpful to you.

Sincerely,

Matt Powell
Eaton, Powell & Tirella
304 Plant Avenue
Tampa, Florida 33606

Your wife cannot be successfully sued, assuming she is not a titled owner of the vehicle. Florida law provides that both the driver and the owner(s) of the vehicle can be found responsible for any injuries caused by a negligent driver. Florida recognizes the Dangerous Instrumentality Rule, which applies to all types of motor vehicles and deems the owner equally responsible with the negligent driver. Since the other driver apparently ran a stop sign, that other driver and the owner of the other vehicle will share responsibility for paying for your injured passenger's damages.