We tested a series of nested model comparisons, where we assessed differences between EOP and low CP youth in: (a) the auto‐regressions; (b) the cross‐lagged associations; (c) the prenatal predictions to ADHD symptoms; and (d) the postnatal predictions to ADHD symptoms of ‘unhealthy diet’ and IGF2 DNA methylation. This evidence concerns the gene IGF2 and attention deficit-hyperactivity disorder.