This is so sad, thankyou for the reminder.
Just in case it helps anyone these are my best rabbit keeping tips, to add to the others:
When you get a hutch, line the floor with an offcut of vinyl. This needs to be glued down properly with an acrylic floor tile glue or similar, so nothing gets under it.
It makes cleaning out really simple as nothing soaks into the wood and basically it never gets saturated or anything - always a dry floor for them.
This is best when combined with a litter tray. We have a large one in our large hutch, for 3 rabbits, and they are brilliant at using it. I put wood shavings in that and just a few shavings and some hay in the rest.
The main floor rarely needs cleaning out, every few weeks really, though the tray obv gets wet and yukky every couple of days. Just empty out (into compost or bin), rinse out under outdoor tap and refill with shavings. Simple.
lastly I don't know if this theory holds out, but we have three rabbits together and they seem often to clean each other's bottoms. Therefore I feel it might be an extra precaution against nasty build up of poo or whatever.
And never feed your rabbit lettuce, it's really not good for them and will give them diarrhoea. Ours have standard pellets from farm supplier and greens or carrot or apple. They are never runny.
Hope your rabbit recovers, Tortoise.