Have you considered investing in a van that can move your entire family? Perhaps a Ford E-Series passenger van?
I'm in Canada.
In my country, I think it's only legal to drive with as many passengers as you have seat belts.Built to provide seating for 7-, 8-, 11-, 12- and 15-passengers, E-series Wagons get people moving to where they need to go.
I'm in Canada.