Breakage coincidence

My wife and I were visiting my elderly mother in Eastbourne a week ago, where she has lived in the same house for 27 years. The house was not new when she moved there, so both her downstairs and upstairs toilets have been there longer than that. I had to take my mother to the local GP's surgery that morning to have a leg wound dressed. Before leaving the house, I used the upstairs toilet but when I flushed the toilet, the handle broke. Removing the cistern lid, I saw that the plastic arm connecting the handle to the flushing mechanism had snapped. I told my mother about this and we both agreed that this was just bad luckand that it had clearly just worn out after so many years. We set off for the surgery, leaving my wife at my mother's house. While in the GP's waiting room, I received a text from my wife saying that she had just used the downstairs toilet, prior to going shopping, and that when she flushed the toilet, the handle had broken! This was within an hour of the handle of the upstairs' toilet breaking. On returning to my mother's house, I inspected the breakage and discovered that, once again, the plastic arm connecting the handle to the flushing mechanism had snapped. While both toilets would have been installed at the same time, no doubt when the house was built, and the plastic would have had a similar life expectancy, the toilet flushing mechanisms would almost certainly not have been used an equal number of times but, even if they had been, what were the odds of both plastic arms snapping in the same way within an hour of each other after so many years? We could not believe it and nor could the plumber who came this week to repairs the toilets.