Mr & Mrs A bought their first house and took out the mortgage cover recommended by their lender.  Absolutely nothing wrong with that except the cover they have is "joint life".  This means it only pays out on the death of the first person and then ceases - leaving the surviving partner with no cover at all! 

Now Mr & Mrs A went on to have children and Mrs A had a few periods of ill health, nothing serious of course, just wear and tear and the riggers of raising children!  However, now that she's a little bit older with some minor medical history to report, any insurance she takes later in life is likely to be far more expensive, perhaps so much so she isn't able to afford it.  Also, as the Mortgage cover was only ever designed to pay off the Mortgage (which it did taking some financial stress off Mrs A just like it was designed to do) it didn't allow for the ongoing loss of Mr A's salary, nor the time Mrs A needs off work to grieve and help the children through this tough time, or cover the additional childcare costs or reduced hours Mrs A has now she's a widowed parent.  This, of course, is a bleak picture and we hope we never have to see one of our clients in this situation especially as it could have been made so much easier simply by having 2 independent life policies with a fixed amount paid (and not just the Mortgage) and in most cases, early on this doesn't cost more than a few pounds over what they were paying in any case.