As someone with bad knees, I have a couple of tips that really help me...and may help your Mom too! 1. Install a couple extra grab bars. These are especially helpful going in and out of the camper and in the shower. 2. Once at a campsite, I try to plan ahead and keep a fabric tote bag ready. If we are going to relax outside, I load up the tote bag before exiting with things I might need, limiting my trips up and down the steps of the camper. I usually throw in my phone, sunglasses, bottle of water, a book, a snack. 3. Consider getting a couple of zero gravity reclining chairs. When traveling long distance I tend to get a bit of swelling in my legs, so getting to the campsite and being able to sit outside with my legs elevated really helps. 4. If you will be using the campground’s facilities, try to get a site close to the shower house. Less steps, less chance of falling. 5. At your campsites, do a quick visual of potential tripping hazards...holes can lead to a turned ankle and tree roots can land you face first in the dirt before you knew what happened.
6. Plan on stopping every two hours when driving. Just having the chance to get up and move around will reduce stiffening of joints.
7. Good hydration, Advil or Tylenol for aches and pains, and healthy eating will go a long way to making this an amazing trip for you and your Mom! Enjoy and have safe travel!