'I feel extremely sad and sorry. Having attended this court for a month now, every day is miserable,' said Tsui Po-ko's mother, who took the witness stand for the first time in the inquest into the death of her son and three others. Cheung Wai-mei, has been a constant presence at the marathon hearing since March 15, when she walked into the courtroom unrecognised by journalists. Tsui's wife, Li Po-ling, only appeared in the courtroom for the first time yesterday. Five minutes after the hearing opened, everyone inside the packed courtroom turned their heads as Ms Li quietly entered the court and took a seat in the front row of the public gallery. Dressed in a black blouse and grey long skirt with her hair tied up, she quickly asked a policewoman sitting next to her in an almost inaudible voice: 'Will anyone take pictures outside?' The officer whispered into her ear, but no one could hear the reply. About 20 minutes later, Ms Cheung was called to the witness stand from her seat, reserved for the deceased's family, passing her daughter-in-law as she made her way towards the stand. The two had been holding hands tightly, giving support to each other. Dressed in exactly the same outfit she was wearing when she entered the courtroom on her first day - a blue denim jacket over a roll-necked black sweater - Ms Cheung was bombarded with questions about her financial situation and that of her son. Throughout the inquest over the past weeks she has appeared calm, but she finally lost her composure yesterday. Coroner's officer Arthur Luk Yee-shun SC asked why she handed her son HK$150,000, which would have been a huge sum for someone who had retired six years earlier. 'Frankly, I treasured every dollar very much,' she said, before stopping, unable to hold back the tears. But she regained her composure and continued: 'I never wanted to control this money and I trusted my son.' The 61-year-old often looked to the ceiling or down to the floor, and struggled to recall the details of the financial transactions and the dates on which they happened. She mostly replied 'I can't remember' or 'I don't know'. Finally, she was asked by lawyer Daniel Wong Kwok-tung, who has been assisting the family since the police began the investigation, asked the key question: 'Do you believe Tsui Po-ko was responsible for these cases?' 'I won't answer this,' she replied. 'No matter what, I love this son and I want to experience this [hearing] in person. After all, my son has already passed away. 'The only thing that he has left me is that he was my son, and I must remember that.'