Thanks for the clarification, Jane!
BTW, I'm a Scout camper too. Over 300 nights as a kid and dad although I'm getting to the age where I can still do it but I don't want to if I don't have to....
It's not too long but my point here is to confer with your local family. WDW is great tent/popup camping January to about April. (we have normally gone in the spring during this time). By May it's pretty warm at night (by my standards in Alabama) and the summer months are pretty uncomfortable unless that's the only time of the year you can come. You can do it but you probably need a cooler - the Trading Post sells ice for about $3 a bag. If you can rent a car or have transportation, you will need to resupply food/water/etc during a stay of that length.
Don't plan to do a park day every day all day. It will wear you out. The Fort is great for tent camping Jan-Apr and Oct-Dec (what I call the shoulder seasons). Plan some full non-park days for the Fort (swim/explore) or head over to Dis Springs or play putt-putt, etc. I know you're coming a long way but a relaxed approach in the shoulder season will pay off.
Bama Ed