Our 19-year-old cat Zoë sometimes wails quite loudly; it sounds just as if she were being tortured but there is no indication of any distress -- she might be walking across the room and give a wail as if she were just saying "hullo". Up to now we have just ignored it, but she has now relocated to my daughter who lives in a town apartment and when Zoë wails at night it wakes everybody (when she lived in our house she was on another floor and behind two doors, so it didn't bother us).
Zoë is stone-deaf and suffers from hyperthyroidism (for about two years now; we feed her Hills Y/D and that seems to keep her healthy enough). The wailing dates from before both her deafness and hyperthyroidism but seems to be getting worse. Every indication is that she is content in the apartment, she seldom went outside even when she could. She sleeps a lot (unsurprising given her age) but she is social and affectionate.
Does anyone have suggestions?
Edit: My (sleep-deprived ;-) daughter wonders if Zoë could be dementing. Also whether some sort of tranquilizing/calming product would help.