Goodness me I could be on a roll here, with my deal about Disabled Railcards nearly at 2000 degrees!
So, having helped my mum get her disabled railcard, I booked tickets for her and her older 84yr old sister on the train from Waterloo to Yeovil. Because of ny aunt's difficulty walking we use a wheelchair to get her between points. So again I did a little research. There is a service offered by the railway companys called 'Passenger Assist'. It is completely free. I telephoned them and explained about the difficlty my mum and aunt would have with the wheelchair and bags. They took the details of the train journey we had booked. Really helpful on the phone. Today when we arrived at Waterloo we spoke to a guard to say we had booked Travel Assist. He spoke to someone on the radio and a lovely lady appeared. She pushed my aunt to the right carriage, helped them on with bags. Found them seats with a table etc. She said a lot of people don't know about it and the more who use it the more secure the future of it will be. Anyway once settled on the train, she liaised with her counterpart at Yeovil.
When mum and her sister stopped at Yeovil, my mum said a wonderful man jumped on. Carried their bags off, helped them off train (I had taken wheelchair back). All before the train carried on to the next station which is always a worry for my mum - that they and their bags can't get off in time. He carried bags and helped them out of the station to the taxi rank. Mum said she can't believe how helpful they all were.
The service is free, but they do need 24hrs notice. Link is to the contact details. You don't need to be registered disabled, just need support to use the train so particularly ideal for frailer passengers.
Fabulous free service :-)