If they go through the trouble of actually suing you and obtain judgment against you , they are able to attach to your bank account(s)....any bank account with your name associated on it, even if it's held jointly; garnish your wages ; and in California they may garnish up to 25% of your State Income Tax returns.
After judgement, the collectors are allowed to keep taking your money until judgment is paid...even if it takes the rest of your life.
They can't seize money from Social Security payments; disability;unemployment; Federal, state or government aid however.
Also, if it's a minor's savings account (UTMA)......I'm not sure that they can touch it.
I'm assuming it's credit card debt....you didn't state how much you owe but it might be worth it to contact them and negotiate a settlement that's realistic for you to repay and avoid being sued. Usually when the collectors begin contacting you, even though they may threaten to sue (and they can), it costs them money to do that and they are usually just trying to force a settlement instead anyway.
Just a note: NEVER, ever give them permission to electronically receive payment from your bank account. Get everything in writing and pay by Cashier's check.
Been there, done that !