This is literally not true. I think you're trying to claim it's not a big deal because most children who contract covid will not die in this way. But this doesn't have any relationship to the statistical analysis of significance that tries to determine causality. In your hypothetical you've stipulated that covid19 is 100% at fault. There's no need for statistics in this case because the confidence at 100% i.e. somehow science has proved the mechanism in your hypothetical.

> Again – statistically, with our current knowledge, children in general do not have much to fear from this virus.

You could have said the same thing about AIDS. Statistically with current knowledge circa 1981 straight people had nothing to fear from AIDS. Statistically in 1983, years after the initial outbreak the proportion of people dying from AIDS as opposed to those who were living with HIV was infinitesimal. And then people started dying at higher, alarming rates. That took over a decade. (https://en.wikipedia.org/wiki/HIV/AIDS_in_the_United_States#...)

I'm not saying covid is AIDS, but we're mere months into this thing and noticing strange syndromes in children. To blanket claim that "statics show us" anything with the certainty you're projecting is shortsighted.