How is age represented in the extract of white girl?

The opening scene see's a establishing shot, in this shot we see a small figure of a young girl on her bike making her presence into the frame of the camera shot. As this is happening there is non-diegetic music playing in the background which connotes the theme of childhood. 
The next shot we see is an extreme close up of the girls trainers where she is pedaling at quite a speed, this suggest to the audience that she is a thrill seeker and represent all children at her age love to do everything with high energy. The camera shot then shows the audience a low angle shot of the young girl enjoying her time on the bicycle as the sun is shining in the background as well as music playing reflects on her upbeat attitude. 
In the same scene we see the girl enter what seems to be a small cafe and the mood changes to a more darker and suspicious scene, this suggest that the girl may have a mysterious relationship with the shopkeeper which might develop later on in the narrative.

The next scene the audience watches the girl enter a room with adults where she seems to act more timid around, this suggest the range of power which children have towards the adults in this particular household. As the girl hands over some money to the father there is a reverse shot which shows the relationship which the father has with his children. In this shot we see a modern working class family living in a council estate where all the rooms looks very narrow. 

The scene then cuts away at a pace and the mother and the children are now on a run, this suggest that danger which they (the mother and children) are in when the father is around. In this shot we see the adults being more of the child and the kids being the mature ones keeping quite and doing as they are told. We also see the girl holding on to a soft animal toy which suggest this is more of the children's side of comfort rather than being at home.

When the family arrive at the new house without the father, the young girl shows a more mature side of her as she argues with her mum to fight for her place in the household like how a young adult would do, she then flings herself onto the undone bed sulking which suggest that although she may think like an adult the girl has her moments of having a natural child behavior.

In the next scene we see the use of ellipsis as the girl falls asleep, to make the scene feel as though it is running she looks out the window where she can see her mother and friend having an adult conversation about alcohol and drugs, this suggest that as a child she shows her vulnerability of being in raw adultery subjects which might put herself in danger when her mother is not around.