I keep seeing Yumna's face. Ever since she first flickered onto my computer screen. The panic and the fear behind her clear eyes is so powerful, I feel it too.
Yumna is a little girl who lost her parents in what is alleged to have been a chemical weapons attack on a neighbourhood in east Damascus. She regained consciousness in a local medical centre a few hours later. She shouts out - 'I am alive!' - almost to convince herself. Then she asks the doctor to help her, and to hold her. She is bewildered, incoherent, terrified. There are more screams. In a city full of horror, she is crying out for humanity.
The pictures of Yumna are among hundreds of images, mostly filmed by survivors, of how people have suffered and died in Damascus this week.
Opposition groups say that in the early hours of Wednesday morning, government forces unleashed a barrage on the rebel-held areas of the city, a barrage which included rockets filled with poison gas. The government says these claims are baseless - made up by the rebels to divert attention from their losses.
Whatever the truth, ITV News has obtained more horrible images of the aftermath. Bodies strewn over doorsteps and streets. Families who died together as they ran. A mother clings to her baby, frozen by the terror they tried to flee.
In one piece of footage, there is the remains of a missile. Locals tell us it was one of the rockets that delivered the poison. There are no visible injuries on the dead. Their faces are twisted. It is impossible to know for sure, but it looks like a gas attack.
There is a small group of people who are in Damascus right now who would be able to find out for sure. UN chemical weapons inspectors arrived on Sunday for a visit which is due to last two weeks.
They had been scheduled to visit three sites where chemical weapons are said to have been used earlier this year. Their mandate is limited to investigating whether such weapons have been deployed, and not to make any judgements on who might have used them.
The world wants the inspectors to be allowed to visit the site of the latest alleged attack. The UN has sent its disarmament chief to Damascus to try to persuade the regime to let that happen.
Even the Russians, Bashar al-Assad's strongest ally, are saying that the UN team should be given access to the site.
A terrible crime may have been committed in Damascus this week. And when the city finally recovers from the trauma, when the fear has gone and the nightmares have stopped, Yumna might want to know the facts about what happened to her family.