Lorraine
well , both are done by the DWP, and as they are both about what you can and cannot do it is possible they could use a decision on one to suggest that the other needs to be looked at.
However tribunals have frowned upon this being done , and they are totally independent . In some cases they have threatened the DWP with contempt of court for not appearing.
As you seem to have got help in the "real world" , read that leaflet , and follow it's guidance .
Telephone the tribunals Service and ask them for advice on protocol , and the fears you have , as they are very helpful.
DLA is not awarded just because you suffer from a particular diagnosis but on the limitations that the health issues cause with regard to mobility and care.This will be different for each person.
There is nothing stopping you submitting further evidence, including a diary of issues you had, and statements from people who care for you etc . But remember this must be based around the time of the original application and decision.
Any evidence will need to be sent to the Tribunals Service NOT the DWP.
You really need to talk to a welfare rights worker face to face for detailed advice .
Rich
"The difference between 'involvement' and 'commitment' is like an eggs-and-ham breakfast: the chicken was 'involved' - the pig was 'committed'."