As the only available witness, four-year-old survivor Zeena al-Hilli may hold answers to the tragic case in which her parents and grandmother were killed in the French Alps.
MSN News asked Zoe Hawton, counsellor and child trauma specialist, how the French authorities will go about questioning the vulnerable young girl.
"Their first priority will be to reduce further stress and trauma for the child," says Ms Hawton. "With that in mind they'll be waiting for the girl to bring up the event herself.
"When she is ready to talk it must be at her own pace, and with a highly skilled clinical psychologist who will have lots of experience in this type of case.
"Without the necessary vocabulary to describe the crime they'll be looking to find ways she can communicate her memories without words. This could be through play or art therapy where they might ask her to draw pictures or to show the event with models," explains Ms Hawton.
"With most children after a traumatic event, at first they aren't able to recall much at all. Instead she might have a central image - just one picture that sticks in their mind, and that picture could be of anything and is often something very small."
The aim is to access this central memory and begin building a narrative around it - to start trying to extend the memory to what's going on around them, perhaps what they can hear or smell while this is going on.
The young girl will almost certainly be suffering from post-traumatic stress, says Ms Hawton.
"What she experienced is way beyond her mental capacity and far exceeds normal human experience. Obviously at four-years-old she won't understand what has happened, but she will have sensed the extreme violence and distress of those around her.
"She's had all her attachment figures suddenly removed, so for her benefit the police will now be looking for someone familiar she can spend time with as well as the psychologist who will be looking to build up a relationship."