"His father used to teach at the university..."

our friends told us. We were out at lunch yesterday at the same tiny place we had visited once before. It really is lovely but I wonder how much longer they can keep going. 
The father of the man had come in to take some photographs to put on a website for them. Yes, they are trying hard but there simply isn't enough space and it is just the two of them. They can't afford to employ anyone to help.
And yes, eventually his father came in. I looked at him but I wasn't sure so I said nothing. He would not have remembered me anyway. He didn't actually teach me. I would have been just one face in a lecture room with about two hundred other students. The teaching, such as it was, was done by the tutors. He might have given ten lectures at most and they didn't stay in my mind. I remembered him more as perhaps being a colleague/almost-friend of another member of staff. I also remembered him as being taller and darker - and younger of course. Well it was a very long time ago. 
And, as I said, I was not quite sure. What was his given name? I knew it was something a little unusual. And then, as he was driving off in his car I remembered the name. I double-checked with the wife when she came out to farewell us. (They know our friends well and we all get a warm greeting and reluctant farewell.) 
"Yes! Why didn't you say something?" the wife said.
"I wasn't sure," I told her.
"You should have asked."
No, we had a little chat in the half which is shop and he didn't know me. He would, no doubt, have been polite and perhaps pretended but it would have made the conversation awkward. As it was we had a pleasant chat. 
Perhaps some relationships are best left that way.