Paying my brother to care for my dad

I'm new to the board and want to say thanks in advance for reading this and offering any advice.

My brother, Rod, lives with my dad, who is 84 and nearly blind. He has no mental issues. Due to his eyesight, he requires a good deal of help.

My brother is paid from a small trust set up to cover Daddy's care. If my brother didn't care for Daddy he would live in assisted living, which we (there are five siblings) would prefer not to do, but are open to if need be. Rod likes the job, but it is often challenging.

Here is the issue: as it's now structured one of the siblings acts as a defacto boss to Rod in terms of raises, bonuses, time off, etc. This has inevitably led to conflicts and hurt feelings (does he deserve a raise? maybe, maybe not). What I'm trying to find are any examples of how others have structured similar arrangements so family relationships stay in tact and the caregiver is treated fairly.

Thanks again for your time.

Sam