Any yea, somebody here is going to say he deserves it. Whatever. The relative has been there for me when I needed help, and it would be nice to keep him around a while longer.
p.s. 13 year old unvaxxed relative in the same household got covid at the same time. Has the sniffles and is fine.
Only needs D if it is winter where he lives or he does not get sun on his skin. I looked much into dosing. I advise 1000 IU 1 to 2 times daily. More small doses is better than fewer large doses. Take it with K or a food containing K because D moves calcium into the bloodstream and K moves calcium into the bones. I would get a vitamin combination with both D and K.
I haven't seen anything about other vitamins or minerals. -- except 'miracle mineral' chlorine preparation. Ignore that.