Childhood brain injury organisations recognise the huge differences in experience and prognosis related to when, exactly, in childhood, brain injury happens.
As well as the differences between childhood and adolescence.
This is also recognised in some of the literature endorsed by Headway, notably the section on the special considerations on Childhood Brain Injury in the Brain Injury Handbook.
If you are too young to remember your brain injury you may never find out or may not be told for many years afterwards, a reflection of the fact that people do not want to be held accountable for what happened to you or to recognise that you may not have fully recovered (the you must have recovered by now syndrome).
As far as your own contribution to causing your brain injury there is also an increasing responsibility as you get older.
Before about 3 months old you are unlikely to be able even to crawl. 4-8 months, you can maybe crawl a bit, and so on.
Obviously if you are tiny (e.g. under 3 months old) you will have made no contribution to your brain injury.It is others who will be entirely responsible.
Someone I have known can remember their traumatic brain injury happening at 3 years old and having to get new glasses and having new difficulties after that.
Even at 5 years old, as I know, you may remember some of the injuries you have had. However, I did not find out about the skull fracture and temporal lobe traumatic brain injury (including swelling and hospitalisation for 3 days at the age of one month) until I was almost 30 years old and even then faced the typical family and professional denial syndrome and have had a long battle (18 years almost now) since then to find out the full consequences.
At 10 years old you may have been irresponsible in riding your bicycle and not using a helmet, for example.
Someone aged 13 or 14 may be riding a bicycle, a scooter and even driving a car in a few societies (or be married in some). They might even be appearing on Teen Mum!
Also, later on in childhood and even more so into adolescence, the person will have learnt more skills and there is much more for the brain to recover to in terms of existing learning. It is less likely that the learning process itself will be permanently damaged.
You need to break down the categories much more. My experience of brain injury at 1 month old is radically different from those I have met who had one at even 3 years old, let alone at 10 years old or in early adolescence (11-14, depending on the individual).
This is before considering gender differences, etc.
Yours
ADW