I'm not an attorney in Minnesota, but in many places, such as Washington, driving with a revoked and/or suspended license is punishable by jail time. You should urge your relative to obtain the services of a Minnesota criminal defense attorney before your relative is due in court.
Depending on the jurisdiction, the relative may be facing jail time for repeated driving after withdrawal offenses. You should contact an attorney to discuss.
Though it is unusual to be sentenced to jail time for the first DAR, subsequent convictions typically do result in jail time - longer sentences depending upon the number of priors. He should consider getting a good lawyer.