I feel sorry for you and you have you all the right to get angry; it's just human nature. True, a valuable life was lost.
But do not think that this is the first time a patient died cuz of the negligence of the doctors in SL. At least every month, we hear a similar story, so next month it could be an adorable child. The problem with SL government doctors is, they clearly lack accountability in contrast to developed countries. On the other hand it is the fault of the relatives/ friends of the patient too, as they do not at least lodge a complaint with the hospital authority, when they have all the right to do so at no cost.
So if you think your sir died due to the negligence of the doctors, just go ahead and lodge a complaint with the hire authorities of the hospital and the health ministry, so they would give those careless doctors a hard time in return by at least investigating them and hopefully punishing them. That way you will be relieved that you did the justice to your late sir.