This is what Mum texted me last night
"New development, on exertion ie going to litter tray she had coughing fit like a patient with heat failure or COPD, happened last 2 occasions.
tonight it floored her completely, was laying with her head on floor so carried her back to sofa"
My dad has gone to collect some recovery food from the vet (the slop in the tins). Mum will try and get her to eat some tonight
but i think the old girl is giving up now