Unfortunately you're just gonna have to decide if you want to continue working with the family or not. You can offer that they pay for full-time spot but just come the days that they want and if they want an extra day to run an errand or have an appt, then they can because they're paying for full time. But unfortunately if they only want to do part time and you financially don't want to provide part-time then you will have to let them find another daycare or if you can swing part-time for them then by all means take them. I know it's a tough decision I've been there myself!