Veteran singer SP Balasubrahmanyam has tested Covid-19 negative, but continues to remain on ventilator. The news was shared by his son SP Charan on Monday in an Instagram video post.In the health update, Charan added that his father39s lung function has not improved enough to be taken off the ventilator."We were hoping for good news over the weekend, we were hoping for dad39s lungs to improve as they were to a certain point where we could remove the ventilator, but unfortunately, we are still not at that point where we can rid him from the ventilator. The good news is that he is now Covid negative," Charan said in the video message."I had previously said that it now doesn39t matter if he is positive or negative, as we are hoping for his lungs to heal fast. They are healing, but they are taking time. Other than that, over the weekend we had a small celebration for mom and dad for their wedding anniversary.""Dad is watching a lot of tennis and cricket on his iPad he is happy that the seasons have started and is looking forward to the IPL. He is writing and communicating a lot and is not under sedation. He is very clear and bright and physiotherapy is going on," Charan shared, thanking for all the wishes and prayers for his father."Let39s keep the prayers going," he said while signing off.SP Balasubrahmanyam tested Covid positive last month. He is undergoing treatment at Chennai39s MGM Healthcare.