Ronald Bowman's son Nick says staff at Panteg County Hospital should have kept a closer eye on his father, especially since he had tried to leave the hospital on two previous occasions.
Mr Bowman's shoes were found on the bank of a river near to the hospital. Three weeks later, his body was found four miles downstream.
Nick Bowman says his father had become "increasingly agitated" in the weeks before his third disappearance, and may have been trying to return home.
The constant reassurance from medical staff that she should not worry as he was being well looked after, calmed my mother down.
My family and I are incredibly hurt and distressed that after my father was admitted to hospital with meningitis, and seemingly making a recovery, he was left without any of the basic care that he deserved and he needed.
My father should have been cared for by staff at an appropriate level. My father was supposed to be checked on by staff every 15 minutes.
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