Li Wangyang's family and supporters have been placed under close watch in the run-up to the Hunan labor activist's first death anniversary on Thursday.
Li, according to a probe, committed suicide while under police guard, just four days after he vowed to press ahead in his fight for universal suffrage in the mainland.
His sister, Li Wangling, has been under close surveillance since then and prohibited from contacting outsiders.
But she managed to give an interview to iCable, in which she recalled her late brother.
"He once said he would not get married unless China enjoyed freedom and democracy, so he was still single when he died," the sister said.
New video footage also shows the late activist, looking frail and weak, being released from jail and being fed and cleaned by his sister.
"Since my brother died on June 6 last year, I have received much support from many people in Hong Kong who were complete strangers," she said.
"I feel blessed."
A longtime friend, Yin Zhengan, who was released from house arrest only recently, also mourned Li's death in Guangzhou.
Yin - who had joined Li 30 years ago in their fight for democracy and had once escaped from jail with his friend's help - stood on the bank of a river and tearfully called out Li's name.
"Rest in peace," he said several times as he placed a lit candle in a paper boat and put it in the river.
Li spent more than 22 years in jail after taking part in the Tiananmen Square protests in 1989, and his death last year sparked protests in Hong Kong.
He was freed from jail about two years ago, but came in for round-the- clock police surveillance after restating his commitment to democratic reform.
His body was found by relatives in a hospital, where he was being treated for heart disease and diabetes, with his neck tied in a white cloth hanging from the bar running along the top of a window. His feet were touching the floor.
Friends refused to accept he had committed suicide and accused authorities of rushing to cremate Li's body three days after his death.
Apart from street protests in Hong Kong, thousands around the world signed an online petition calling for a thorough investigation into the circumstances of his death, although authorities insisted Li committed suicide.