If you fail to appear in court, you could be subject to a contempt order resulting in a bench warrant. And often people who are picked up on bench warrants on the night or on a weekend have to spend time in jail before they can be taken back before the court.

Odds are, though, if this is a collection suit, the judge would issue a default for non-appearance. There might subsequently be a creditor's exam, which your mother could be supoenaed to attend, and failure to respect the subpoena could result in a bench warrant. But if she has assets that can be garnished or executed (seized and sold), and the creditor can identify them without a creditor's exam, that's probably what would happen.