Normal healthy children who don't develop a severe case aren't treated at all, so talking about early treatment is irrelevant. I literally just talked about this with a close family member who is a Children's ER doctor.
>And isolation of sick patient from viral reservoir (such as fomites and other asymptomatic sick) is known to be important too, as it changes the viral inoculum dose.
This isn't known to be important. If a person has been infected long enough that they are already symptomatic then "viral inoculum dose" is irrelevant.