1) pay in advance. Change your pay so you are getting paid before care is given.
2) If payment isn't paid in full and on time there is a late fee of $50/day (including weekends and holidays) and care is suspended until both the tuition payment and late fees are paid in full. Days that the child is suspended fees are still due.
3) set days and/or set weekly tuition payment instead of daily. (min. days paid no matter what. If they need an extra day they pay extra (before care) for that day)
4) have in contract that you have the right to take the client(s) to either small claims court or collections and that all costs for these serves will be paid by the client(s).

Not much help with this client, but will help with future ones