The dad of one of my son's classmates is also into bicycle touring! That gives the possibility of a combined father/son "big" tour.
Although I have a tandem, the likely scenario is four people riding single bikes. The boys are 8 years old now, clearly too young to ride their own bikes, but for future planning, any thoughts on "right" age? I'm thinking old enough to be safe on the road, young enough to still want to go with dad.
Timing would be summer, so I'm thinking Northern Tier, Transamerica, or Pacific Coast. The kids don't get as long of a summer break as they used to, and we live in Southern California, so that would drive it towards being a Pacific Coast tour. I've done most of the Pacific Coast so I realize there's some sections of 101 which would tend to bump up the minimum age. (Though the worst parts are in Southern California, which we could easily skip.)
It's just an idea at this stage, so any thoughts are welcome. We would have the opportunity to do shakedown tours, etc., close to home before going on a big trip.