A maternal physical health condition that predated pregnancy reduces the likelihood that the child loses insurance by 6 percentage points, while a preexisting diagnosed maternal mental illness increases by 11 percentage points the probability that the child will become uninsured.
Emphasis added. The study was of children born to mothers who had government-provided health insurance.
Different types of abilities appear to be manipulable at different ages. IQ scores become stable by age 10 or so, suggesting a sensitive period for their formation below age 10. (See Kenneth Hopkins and Glenn Brecht, 1975.) There is evidence that adolescent interventions can affect noncognitive skills (see CHLM). This evidence is supported in the neuroscience that establishes the malleability of the prefrontal cortex into the early 20s (Ronald E. Dahl, 2004). This is the region of the brain that governs emotion and self-regulation.
On average, the later remediation is given to a disadvantaged child, the less effective it is. A study by Thomas G. O’Connor et al. (2000) of adopted Romanian infants reared in severely deprived orphanage environments before their adoption supports this claim. The later the Romanian orphan was rescued from the social and emotional isolation of the orphanage, the lower was his or her cognitive performance at age 6. Classroom remediation programs designed to combat early cognitive deficits have a poor track record.
Their point is that policies to improve the lot of disadvantaged children should be age-targeted, with an especially heavy emphasis on very young children.