Ashamed that not noticed til today lifted the rug up today (down for about a year) ... no other way to say this bit it was (underneath) soaked in cat piss.
We’d not smelt it (assume soaked through to hide) but it was literally dripping underneath.
Lots of questions re cats (2 - m/f both neutered and not in prime - 13/14 years old but not senile - have a number of trays to choose from and access outside.
Anyone any anecdotal stories specific to sheepskin? Have removed and cleaned area obviously