Makek sure they are using full days and consistent days from week to week so for instance they are coming every Tuesday and Thursday. Then you can put up an ad looking for another child that needs part time care for Mon, Wed, Fri. You can have more than 5 children enrolled in your program provided that no more than 5 of them are at your house on any given day. Make it clear to the part time people that the space is only available for the year till the maternity leave is up. With any luck you will have another family start a leave and still be able to take the part timers.

As far as payment goes I charge slightly more than my full time daily rate. For the mom on mat leave I would probably just prorate it ie reg is $200 a week so $40 a day but charge her regardless of attendance. For the one coming in three days a week it would be $40x3 = $120 so I would probably would charge her $125 for the three days.