Challenging behaviors across COVID-19 in young children with rare neurogenetic conditions: A seven-year, cross-syndrome analysis.

Challenging behaviors are common in rare neurogenetic conditions and significantly impact family life. Families were especially vulnerable during COVID-19, yet little is known about behavior trajectories considering pre-pandemic risks. The Purdue Early Phenotype Study has followed children with and without neurogenetic conditions since 2017, including during the pandemic. Analyses examined patterns and predictors of challenging behaviors among 228 children (Williams = 52; Angelman = 64; Prader-Willi = 29; fragile X = 23; controls = 60), ages 1 month-10 years (57% male, predominantly White), focusing on how prepandemic features predicted later trajectories. Across classes, challenging behaviors increased. Latent class analysis showed that higher-risk family profiles predicted steeper increases in internalizing behaviors. Findings suggest COVID-19 layered complex additional effects onto dynamic early behavioral trajectories in families of children with rare neurogenetic conditions.