I have a joint account with my daughter. Citibank is suing me for unpaid credit card. If they get a judgement, can they freeze this checking account ? They would be taking her $$ too - is this legal to take anothers money when the other joint account owner ha the debt?

If your name is associated with the account.. they can do it if they have a writ of garnishment.

Yes they may freeze the joint account, and then she will have to go to court and prove what money is hers and what money is yours, They will assume most of it is yours till proved different

What about an on-line savings account like Emigrant? How do they find these accounts anyway?