Lynn Harvey's husband Phil died in October 2010 following complications from a triple heart bypass operation in September 2009 at Basildon Hospital's cardio unit.
Mrs Harvey claims that her husband caught an infection in his leg following the operation, and has criticised the treatment he received as being blase and hampered by unneccessary delay.
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Today's showers should clear overnight - and tomorrow will be more settled, but temperatures still feeling cool.
The pair have been poring over old maps and records in their bid to convince the council the warehouse should not be converted into flats.
Wimbledon Ukip candidate Peter Bucklitsch sparked anger after saying the little boy died because his parents tried to "jump the queue".