Controversial former University of the Witwatersrand SRC president Mcebo Dlamini was denied bail in .
The 14-month-old baby girl disappeared in about August last year, though neighbours are not sure of the exact date.
Her parents kept quiet about her whereabouts.
Yesterday police found the baby's decomposed body in a solitary and unmarked grave in Heidelberg, about 30m from the N3 highway.
Ekurhuleni police have arrested the parents of the girl.
"The couple say they did this because they had no money to give the child a decent burial," Inspector Jakub Rasool said yesterday.
The couple live in Duduza, Nigel, and travelled just more than 30km from their home to Heidelberg, where they buried the baby.
They also claimed that they were unemployed and could not afford to pay undertakers.
Police refused to disclose where the couple's relatives lived, saying they formed part of the investigations.
Rasool said they arrested a 21-year-old woman and her 26-year-old boyfriend on Saturday after exhuming the decomposed body of their daughter.
Rasool said the arrests came after a tip-off from an informant.
"We followed up every lead that came through and it was revealed that the child could have been buried four months ago," said Rasool.
He said the child was last seen alive in August.
The body was taken to a government mortuary where a postmortem will be performed to determine the cause of death.
A pair of white socks and pieces of cardboard box were found inside and outside the grave, and police suspect that the body could have been wrapped in them.
"The child's birth was not a secret because she had a birth certificate. But we found it strange that they did not inform the authorities about her death," said Rasool.
He said the couple's parents were aware of the child's death.
"What their parents have told us about the death of their grandchild contradicted what our informer said. We are waiting for the postmortem results before taking any further steps," said Rasool.
He said the couple's parents were also being investigated.
"If the results reveal that the child was killed and that their parents were aware of that, then further charges will be added and more arrests will follow," said Rasool.
The child's parents are expected to appear in the Nigel magistrate's court soon for failing to report a death.