"These slippers I'm wearing are too big, they're slipping off."
She's told me this a few times now. Last time I visited I checked and there was no looseness as far as I could tell, but I made a play of unfastening the velcro and pulling the fold-over tighter, and then Mum was content for another half hour until we went through the same process.
There's little point in me telling Mum that we had to buy them big because her feet were very swollen at the time and may well be again ("Really?" she'll ask, professing ignorance), or even that the velcro can be adjusted ("Well, I didn't know that!"), but I usually do go ahead and explain anyway.
This time she started relaying what I was saying to a member of staff. It went something like this:
"You can adjust them to make them tighter, if you want, Mum."
"Really? Oh... He's telling me that they fit"
"We had to buy them that size because your feet were so swollen a few months ago."
"I don't remember that."
"So... all you have to do is unfasten them and then pull the fastener over a bit further to make the slipper tighter."
"He's telling me that this is a company that takes pride in being one-size fits all and that these are special shoes that can fit anybody..."
I'm almost tempted to speak any old rubbish into the phone if she's going to make it all up anyway.