I am sorry sorry to hear about poor Seth...keep your chin up ....we were given this diagnoses with Bailey at 5 months i was completely wiped out by it.
But after months of hydrotherapy and 15 minute walks no ball etc just straight forward calm walk and medication she really did come on and make huge progress
She is now 6 and doing really well
we have adjusted ours lives and the others know no different only the fact she gets a ride after 40 mins running
Seth has a wonderful mummy that will do her very best for him ...what more could a little chap need
So so sorry...but together you will win the battle
take care Jo