Caregiver providing personal services to dad - he should be the payor (and get the medical deduction).  IF funds came out of estate funds, perhaps that should be treated as a distribution from Estate to Dad followed by payment from dad to caregiver

He is in a nursing home and they are paying someone to "keep him company" while he is there.  Is keeping someone company a medical deduction?

If the caregiver 1) monitors dad to call for help when needed; 2) assists in potty; 3) assists with mobility / wheelchair driving;  4) feeding / drinking; 5) reads to him because he cannot; + other daily activities he is unable to do for himself, then maybe it's qualified medical expense.  I forgot - does private caregiver in the nursing home need to be licensed?

But isn’t most of that covered by the nursing home charges?

doesn't sounds like a medical necessity, but a personal preference to have someone there to keep him company.

Sched A> Med Expense Wkst, line 6 >about line 6>  "(2) medical expenses or personal care services required by a chronically ill individual as prescribed...."  Dr letter should work fine.
My mom is in an expensive assisted living place; she likes to stay in her room, so she gets no attention from staff other than at meals.  We have a helper hired to stay with her and do the daily activities mom cannot do on her own: Transfer from bed to chair; Toilet; prod her to eat and drink more; socialize, etc.  Left alone, mom would stay in bed and never get up or eat / drink.

Been there, done that. They were called Companions. Couldn't feed, just encourage eating. Did nothing but talk and keep company. I wouldn't consider them healthcare.

Businesses issue 1099-MISCs, not individuals.  Neither dad or the estate need to issue a 1099-MISC.