A film released in 2003 entitled "The Mother" starred Anne Reid, which I have read about, but not seen.
You may recall it but if you don't, and don't want what you learn to pop into your mind every time you see Celia in Last Tango, stop reading now 
In the film (she was apparently 68 at the time), she played an ageing widow and embarked on a torrid relationship with her daughter's much younger lover...........Daniel Craig.
She has gone up quite a lot in my estimation since I found this out 