Restoration of parental rights is possible in Georgia.
Reinstatement of parental rights in Georgia isn't possible.
Possible doesn't mean probable.
Every State has statutes providing for the termination of parental rights by a court. Termination of parental rights, which can be voluntary or involuntary, ends the legal parent-child relationship. Once parental rights have been terminated, the child is legally free to be placed for adoption.
Approximately nine states have legislation in place that allows for the reinstatement of parental rights (Georgia isn't one of those nine states) following termination of parental rights. If a permanent placement has not been achieved within a specific timeframe, a petition may be filed with the court requesting reinstatement of the parent's rights. If the court determines that the parent is now able to provide a safe home for the child, the request may be granted. The laws were developed in response to children who were aging out of the foster care system and re-establishing ties with parents and family members.
Frankly, what he is asking about will be very expensive, take months, if not years, and the positive result is highly unlikely.
I suggest he see a family or domestic relations lawyer in your county.
Without a lawyer it's impossible.
With a lawyer, the odds might be one chance out of 100,000.
Reinstatement of Parental Rights in Georgia