Linear mixed models (LMMs) were used to investigate the relationship between prenatal depression and maternal perception of child difficulty at different time periods across pregnancy, 1 day, 4-, 12-, and 24-month postpartum periods. Model parameters were estimated using restricted maximum likelihood estimation in Stata version 12 (StataCorp, 2011). A random intercept model specification was used to allow each individual to have their own intercept and to appropriately account for the dependent nature of the data due to repeated measures on the same individual. As previously mentioned, models for the NPI (pregnancy and postpartum) and PSI (4, 12, 24 month) data were run separately.