If you get called the tell the lawyer who calls you that you have a 'professional fee' that has to be paid to show up at court. LOTS of professions ask for their fees to be paid. We should be NO different. Most lawyers will pay it because, really, all they care about is winning and they just pass the "fee" they have to pay you on to the client in the end.
Ask for a day's wages plus whatever it costs to care for YOUR kids too.