On the blood clots: first these seem to be in a small subset of cases, they are NOT a primary and common symptom. I only point this out to make sure there is no panic. It is being looked at for the cases where the deaths are not from the pneumonia/lung issues. As for Covid toes in infants it is mainly seen in asymptomatic cases. Kids under 14 really are not in the risk group. You may see reports of some exceptions but main advice is keep these reports in perspective. They make headlines, but risk is always measured in numbers. There is a risk in crossing the street and its real, but we do not hesitate to cross streets. Without a context these reports become much scarier than they should be.
As for the clotting, it is too early to tell. If it is a side effect of an overreaction by immune system then ironically people with weaker immune systems (including the elderly and the immune suppressed) may suffer much less from the complications of an overactive immune system than healthy young people whose immune system is too active.
There are multiple axis of events here, I think its easier if they are kept separate in our minds. And again for context even now from the numbers of asymptomatic cases the risk degree is still very low for healthy, young part of the population, so panic is not needed. Caution, listening to experts, shielding the vulnerable and making sure we don’t overload our health care is still the main challenge here.