Hey op.
Ok few things from your update. Sorry if any of this has already been covered. But od rather cover things off than miss things when you've have a new diagnosis.
I'm not sure how old your ds is so some of this may or may not be relevant. If he has only had noctournal seizures there are in some ways better because of the time of day (less risk factors when I'm bad than for example crossing the road)
The recommendations is to not leave a newly diagnosed person alone in possibly dangerous situations so to be clear. (Untill there seizures are stable)
So don't leave alone in the bath (shower is safer in case of a seizure)
Don't leave alone in or near a swimming pool, beach, water source in general
Don't leave alone near stairs or things that could be fallen down
Don't leave alone near roads.
Don't leave alone near boiling water
All pretty logical.
With regard to rectal diazepam assuming it's the pippet type id you need to use it if possible elevate ds bottom slightly and remember to keep the pippet squashed so the medicine doesn't go back into it.
Sodium valporate is an older style of drug ie its been around for years, this is good it is avaliable everywhere (normally with a prescription obviously) it is well know and any side effects, contra indications etc are well known.
Start keeping an seizure diary. Record Everything what he's eaten, what he's done, mood etc. It will help you pin point triggers. Triggers vary from person to person but some of the more common ones include.
Tiredness
Excitement
Certain foods (eg caffine, sugar)
Heat (eg over heating)
Being upset
Just to be clear nocturnal seizures refer to a seizure than happens when asleep so it can happen during day time naps too.
Other things to remember seizures are bloody knackering (i say this an an adult with a epliepsy) depending on how the effect ds he may need up to 3 days to recover after a tonic colonic seizure.
Absence seizures or partial seizures take many forms depending on where in the brain is effected. What you may see is really too long to list here.
If you want to ask anything or talk about anything please feel free to pm.
Hth