A 17-year-old died during the protests in Iran and the family found the body 10 days later.
In addition, the same family have reported that the security forces have stolen her body to bury her secretly in a village.
Nika Shakarami disappeared on September 20 after taking part in Mahsa's memorial protests in Tehran.
In her last message from her to a friend of hers she had said she was being chased by the security forces, she told an aunt, Atash, to Bbc Persian.
After 10 days, the body was found in a morgue of a detention center in the capital.
"When we went to identify her, they didn't allow us to see her body, only her face for a few seconds," said the aunt.
Nika's family then moved her body to her father's hometown Khorramabad in the west of the country on Sunday on what would be her 17th birthday.
At that point, a source said, the security forces ordered family members not to hold a funeral ceremony, but despite the reassurances, they "stole" the body to bury it in another village, Veysian, 40 km away.
And they arrested her aunt, threatening to kill her if the rest of the family participated in her protests.
Hundreds of protesters nonetheless gathered in the Khorramabad cemetery and chanted anti-government slogans.
