DNA results released by the Alexandra Clinic on Friday have revealed that the infants in the baby mix-up were in fact not switched .
Two mothers gave birth to baby girls last Sunday but the nurses on duty forgot to strap their identification tags on their wrists.
The mothers were allowed to take the babies home, but one of them died last Tuesday while in the care of Lebo Nkadimeng, 23.
"We still can't believe that it is our baby who died. We were only told about the results on Friday. We would like to see proof," said the dead baby's father, Wandile Zulu.
Zulu said they would prepare for the funeral only once a second test confirmed the identity of the baby.
The family believe the baby could have survived had she received medical attention in time.
Nkadimeng said the infant started vomiting and foaming at the mouth on Tuesday.
"I took her to East Bank Clinic, where we waited for two hours in the queue. By the time a nurse was available to attend to her, she had stopped vomiting.
"I was told to take her home and then to Alexandra Clinic if she started vomiting again," she said.
Nkadimeng said the baby would not wake up an hour after she had returned from the clinic. She took her to Alexandra Clinic, where she was declared dead.
The East Bank Clinic could not be reached for comment.
Chief operations officer of Alexandra Clinic, Dr Muvili Simba, said Nkadimeng "has not been honest from the beginning".
He said she left the clinic on Monday convinced that the baby was hers and he had insisted on conducting DNA tests to be certain.