Taminator, it really helps to raise the feet and legs. TEDS stockings help some, but raising them, and if they're cold, wrap a heating pad around them. The muscles atrophy and no longer are able to pump blood back up from the feet, causing the blood to "pool" in her feet. This all of course, is in the case of ALS causing feet to quit moving. If she's immobile, I'm presuming she doesn't walk "naturally".
My feet went first, and I do have off and on odd sensations. I mostly feel like I have tightly laced boots on my feet, at times when they're totally unbound, as in bed with a blanket rack keeping the covers from laying on them.