“…Higher levels of family irregularity hamper the ability of young children to develop a stable sleep onset and good quality sleep during the night (Billows et al, 2009;Buxton et al, 2015;Gregory, Eley, O'Connor, Rijsdijk, & Plomin, 2005;Spilsbury, Patel, Morris, Ehayaei, & Intille, 2017;Staples et al, 2015). Additionally, separate studies also find that family irregularity is associated with child psychopathology (Ivanova & Israel, 2006;Rijlaarsdam et al, 2016). While studies indicate that associations between sleep and child psychopathology are likely to be bidirectional (El-Sheikh & Sadeh, 2015;Gregory & Sadeh, 2016), several studies show that specific symptoms sets of developmental psychopathology, such as ADHD or autism spectrum disorder, might be underlying sleep problems and not the reverse (Owens, 2005;Richdale & Schreck, 2009;Verhoeff et al, 2018).…”