This probably ought to be in “Small Talk” . 
Our latest gite guests (new this year) are leaving today. We invited them for aperos yesterday evening and we happily gossiped for a couple of hours about our respective lives. During which gossip we learnt that a few years back their daughter bought a house in Wimbledon in a street we knew. After a few minutes of confusion - trying to remember the number and which side of the road it was and which half of a semi it was we discovered - their daughter had bought OH’s sister’s house. 
Only one phrase for it - “small world”.
. We have had people and constant changeovers since May, so looking forward to staying in someone else’s gîte!