Improved life expectancy for the whole population, not for that children. If a child dies at 10 instead of 2, the population life expectancy at 0 will be great

Improved life expectancy for the whole population, not for that children. If a child dies at 10 instead of 2, the population life expectancy at 0 will be greater, but from 10 - the same. Heck, even if dies at 80 instead of 2, this does not say anything about health, just the fact some dangerous early-life condition was addressed.