Dozens of families have contacted ITV London over the treatment of their loved ones at Basildon Hospital.
The hospital is one of 14 across the country currently under investigation, because of higher than expected death rates.
The probe by the NHS Commissioning Board was ordered in the wake of failings at Stafford Hospital, where neglect and abuse led to hundreds of unnecessary deaths.
Two families are claiming the deaths of their relatives following treatment at Basildon Hospital could have been prevented.
One of those families is that of Lorraine Linder's. Last year, Lorraine was diagnosed with lung cancer, the tumour had spread to her spine and she died within weeks.
"It's watching someone's personality wither in front of your own eyes."
Her family say Basildon Hospital had three chances to spot the cancer earlier and save her life, but kept missing it.
"Nobody listed to my wife. "She was saying she had got a lump in her back and they're x-raying her neck. "Nobody listed to her complain and say well I've got a pain in my back, they would say well it's your breathing."
Jay says he is devastated that it took eleven months to get the diagnosis.
"We were trying to help her, then you realise, there's nothing else you can do. You can't help her anymore can you?"
Lorraine died at home just before Christmas but spent weeks in Basildon hospital, where Jay argued with one nurse, who he claims dished out the wrong pills.
"She looked straight at me and said that's your fault because you were talking to me, and I was like, sorry? "she said, you heard, because you distracted me that's why these tablets are wrong."
Jay is planning to write a complaint. Something Fred Harris's family, have done already.
At 90-years-old Fred had health problems, but his family say Basildon made them worse.
Fred went to hospital, short of breath. During his stay, he was shunted from ward to ward. His granddaughters say nurses did not even realise he was there.
"Because Grandad was moved nine times in 12 days he actually probably didn't even spend more than 24 hours in one place, actually killed my grandad. It helped to"
"He went from being a Royal Marine Commando within hours to being child-like and that wasn't my Grandad."
"He actually said to me, I just feel like a little boy lost, he couldn't understand why anybody, any person, regardless of what profession you're in, would treat anybody like that."
His family claim nurses ignored wounds on his legs. Eventually, Fred developed MRSA. In his last moments, he begged his granddaughters to speak out.
"We're doing it for him because if we don't, people will be sitting in our shoes, going through what we're going through. We can't grieve for our Grandad yet because we need to know answers of why Grandad had to have lack of basic care."
That is what many families are asking about Basildon. How a hospital that aims to cure can often forget to care?
In a statement Basildon hospital said:
"Basildon University Hospital is refocusing every aspect of its work to improve the care it delivers to its patients. "The Trust is sorry if the family of Fred Harris and Lorraine Lindner feel any aspect of their care was poor and will investigate their concerns to ensure any lessons which can be learnt are. "We have started a programme to ensure all patients receive good safe care and their experience with us is a positive one. A number of immediate improvements in the delivery of care to our patients have been made but we want to improve further. "To do this we need to listen and learn and would urge anyone who is unhappy with their treatment or that of a relative to let us know immediately."