The subject of intentional breeding or meat rabbits is prohibited. The answers provided on this board are for general guideline purposes only. The information is not intended to diagnose or treat your pet. It is your responsibility to assess the information being given and seek professional advice/second opinion from your veterinarian and/or qualified behaviorist.
LEADERS: Azerane Bam BinkyBunny JerseyGirl LBJ10 LittlePuffyTail LongEaredLions RabbitPam
Tell him/her to take th ebunny to the rabbit savvy vet. No experienced vet is going to tell someone that a bunny drinks a lot of water out of boredom without checking obvious illness problems first. Offer this link about how to find a good rabbit savvy vet. http://www.rabbit.org/faq/sections/vet.html
The bunny could have a UTI or some other illness.
Also, let him know that white vinegar helps clear out the scent from the box. Yes it smells like vinegar, but that goes away. Of course the vinegar has to be rinsed first before litter is put back in the box.
The bunny also might need it's scent glands looked at and cleaned.
So ultimately, this person needs to find a vet with more experience with rabbits.
I wonder if this has been going on the whole time or if this recently changed.