Education/School help for Y5 child

I have a son nearly 10 years old now(year 5 at school).He was diagnosed with right side hemiparesis, when he was 10 months old.He has achieved most of his physical milestones with physio.He has had speech issues too but he is not in a bad state.He is not very verbally active at discussions in the class.He always has found creative writing challenging.He is doing alright in maths and other things in literacy.I need advice on,could his medical and speech issues be a reason to be not able to process information and put things on paper.I am really worried and need to know, what can be done to help him as this one area is holding him back to achieve his potential academically. We want to help him now, rather see him struggling in higher classes.

Thanks,
Awaiting for a reply with some useful guidance

chakri