Autistic children and their parents are at risk for mental health problems, but the processes driving these connections are unknown. Leveraging three data cycles (spaced M = 11.76 months, SD = 2.77) on 162 families with autistic children (aged 6–13 years), the associations between parent–child relationship quality (warmth and criticism), child mental health problems, and parent depression symptoms were examined. A complete longitudinal mediation model was conducted using structural equation modeling. Father depression mediated the link between child mental health problems and father critical comments (β = −0.017, p = 0.018; CI [−.023 – −.015]). Father report of child mental health problems mediated the association between father depression and father critical comments (β = 0.016, p = 0.040; CI [0.003–0.023]) as well as the association between father positive remarks and father depression (β = −0.009, p = 0.032; CI [−0.010 – −0.009]). Additionally, father positive remarks mediated the connection between father depression and child mental health problems (β = 0.022, p = 0.006; CI [0.019–0.034]). No mediation effects were present for mothers. Findings highlight that the mental health of parents and autistic children are intertwined. Interventions that improve the parent–child relationship may reduce the reciprocal toll of parent and child mental health problems.

The Florida State Twin Registry has existed for nearly two decades, and it grew primarily over 10 years as part of the Florida Learning Disability Research Center at Florida State University. The registry contains 2753 sets of twins and other multiples in Florida. The mean age of the sample currently is 17.96 years (SD = 2.05). The registry is diverse in terms of race and ethnicity (49% White, 19% African American, 24% Hispanic and 8% mixed or other). The characteristics of the samples and measures in the studies that served to build the registry are outlined.

The Florida State Twin Registry began in 2002 through a pilot study of personality disorders and executive cognitive functioning in adult twins. Since 2006, the registry has grown substantially as part of the Learning Disability Research Center at Florida State University that recently began its second funding cycle through the National Institute of Child Health and Development. An update on the Florida State Twin Registry sample, focus, and measures is provided, as well as future directions.