Hi M..I checked out your pics..Really nice C&S's. Sorry, don't know the names of most C&S's..the 1st is a succulent and cactus in one pot..the 2nd is an Aloe..Number 4 looks like what I call a Peanut Cactus..
Though I can't name your plants, I grow numerous sux and a few cactus.
Your soil temp is high but does it drop at night? If you consider the origins of C&S's, most in deserts, they thrive in high temps during the AM, then a 20+ degree drop at night.
Does your gramma also live in NC? If so, and these plants are used to high temps during the day, they should do fine. But most Cactus like the drop at night.
Be careful when watering..do so as early as possible so they have time to dry before nightfall, especially if it gets cold..This is one way C&S's develop root rot.
The soil needs to dry thoroughly.
I'm unfamiliar w/NC's temps..do you bring these plants in during winter or is it warm enough leaving them out yr round?
Cactus can adapt to cold temps, but again, it's important the soil remains dry throughout a cold night. I wouldn't leave out if temps dip below 40-45F. Any colder and they could freeze.
In winter, I keep my C&S's in the sunniest window, (mainly south) in a cool, semi-unheated room/s. I believe a cool winter promotes flowering in summer months.
Are you going to keep them in their homes or repot? LOL..Toni

Thanks for the insight. These plants actually came from western pennsylvania, where I'm from. I've only been here for 3 weeks, so I don't know what the climate is like, but I most certainly would bring them in once night temps begin to drop below 50 degrees F. The night temps have been around 70 degrees F, so they are getting at least a 20 degree drop. Also, I do water in the morning when I can, never in the evening or at night.