Your idea sounds great. Plenty of property, close to family, small enough to take care of and still be independent.
If your property is close to Aurora NC your climate is not too severe but you will have challenges as AS is not really a 4 season trailer.
As already mentioned a large propane tank will help in winter when the cold uses up more propane. You will likely need a dehumidifier which will help with condensation and maybe only need it plugged in during the winter or extreme humidity. Check under the bed between mattress and wood as it can build up there because of the hollow space under the bed. Because it will be stationary you can add as much insulation as your weather dictates. You could also put a skirt around to help with cold air underneath the trailer.
A cover will keep off hail, heavy rain, falling branches, mossy green buildup and a possible unusual flurry of snow. The cover will also minimize leaks that always creep up regardless of how well you seal it.
Make sure to seal up well for critters that may want to live with you or explore your warm surroundings.
The cover and deck also give you the opportunity for outside living and cooking area when weather allows or the trailer feels a little snug.
The image is from Texas Airstream Harbor where lots of folks have a trailer, cover, cabana or rvdominium.
Good luck and keep us posted how this works out.