I know this is done by many - successfully. Try Googling to find some blogs by 'full-time RVers with children'. The blogs are out there but I've never really paid attention to them because we don't have children along. It would be a great learning experience for all of you. You might want to mosey on over to the 'full-timing' forum on this site and perhaps some bloggers will show up.
As for taking along 2 cars, that would be very difficult and totally unnecessary. You can't tow 2 cars behind a motorhome and that would mean you'd tow one and you, yourself, would be driving the other. Not being all together in the same space doesn't leave time for good conservations on what you're seeing out there! It would also be very expensive - double the fuel, registrations, insurance, maintenance.
Good luck and it is definitely doable.
