The first group of four, two men and two women, who were initially arrested on Sunday, appeared on Monday.
The court postponed the case to August 11 for further investigation, said Warrant Officer Basil Seekoei.
“On Monday three more suspects were arrested. They appeared in the same court yesterday [Tuesday] and will appear together with the other four on August 11,” Seekoei said.
All seven face charges of murder and arson.
Neighbours found the two bodies inside the aunt’s house on Sunday morning and alerted police.
The group allegedly set the house alight after the murders, but neighbours managed to remove their bodies.
Police said the adult female was found with stab wounds to the upper body.
The six-year-old was suspected to have been strangled.