Young children are surprisingly resilient against Coronavirus infections, their mortality is so low that it hardly figures in the stats (on an individual level it is still just as much a tragedy).
Age is very significant for mortality rate: 0-9: 0%, ..., 60-69: 3.6%, 70-79: 8.0%, 80+: 14.8%. Also the regional breakdown is apparently a useful approximation of what happens when the healthcare system is overwhelmed (Hubei 2.9%) vs not (other Chinese provinces 0.4%). Also 81% patients reported mild symptoms.