“There is finally progress after waiting for several years,” the woman, who is in her 60s, said. “I miss my daughter every day. The long investigation for over three years really tormented me. I cry every day when I think of my daughter.”

The case will be mentioned at Kowloon City Court next Monday.

Kwan, 35, was thought to have performed a liposuction on Lee at the beauty centre in Kincheng Commercial Centre on Carnarvon Road on June 26, 2014. The dance teacher later collapsed at the centre and was sent to Queen Elizabeth Hospital, where she died.

Lee specialised in Latin ballroom dancing and ran Ka-Ka Dance Workshop in Lam Tin.

Wong said her granddaughter, who was only nine months old when she lost her mother, just had her fourth birthday.

Despite deaths, still no action on Hong Kong beauty industry

“On her birthday she talked to the photo of her mother, saying: ‘Mum, it’s my birthday. Please come home soon … Mum, let me sing you a birthday song.’ My heart ached when I heard this,” Wong said.

She said her granddaughter always asked where her mother had gone and when she would return.

Lawmaker Alice Mak Mei-kuen, from the Federation of Trade Unions, urged the government to hasten its efforts to regulate the medical beauty industry.

The legislator, who has been following up on Lee’s case, said the problems with the industry first came to public attention in 2012, but proposals on new laws to strengthen regulations were stalled in the legislation process.

“The process is very slow,” Mak said. “It could be due to opposition from the industry and vested interests. The government needs to have the political will and determination to work for the people’s rights.”

A spokeswoman for the Food and Health Bureau said a proposal submitted to Legco to regulate medical devices, including those used by the beauty industry, focused on ensuring devices met safety standards before being placed in the market and enabling swift control measures against defective or unsafe medical devices.

“The government does not intend to regulate the use of medical devices,” she said. “The Food and Health Bureau does not have a plan to regulate the beauty industry or beauty services through the legislative proposal.”

She said the Private Healthcare Facilities Bill had been scrutinised by the Legco’s bills committee. Under the bill, hospitals, day procedure centres, clinics and health service establishments should either obtain licences or exemption letters to operate.

She added that the government had been formulating new proposals to regulate cell, tissue and health products for advanced therapies.

DR Group had marketed this medical treatment as a health care therapy said to improve the immune system by injecting enhanced cells that could kill mutated cells before they became cancerous.

One woman died, another had her legs and four fingers amputated, while the third suffered permanent injuries.

Doctor jailed for 12 years over worst beauty treatment blunder in Hong Kong’s history

The same year, the government formed a steering committee to review regulations for private health care facilities in the aftermath of the incident. The panel proposed a new law to identify a list of procedures with potential safety concerns. Procedures on the list would be performed only by registered medical practitioners or under their supervision.

These included procedures involving injections, mechanical or chemical skin exfoliation and hyperbaric oxygen therapy.

Another proposal involved placing 20 types of medical device into four risk categories, with the most dangerous ones to be operated only with a doctor present. These included devices used for popular beauty treatments such as skin lasers, robotic hair restoration and high-intensity focused ultrasound (Hifu).