Although the Australian work
of McIntosh (2010) found that infants under two who spent one
night or more a week and toddlers who spend 10
days a month
of overnight
time in their non-primary caregiver's care are more irritable, more severely distressed and insecure in their relationships with their primary parent, less persistent
at tasks, and more physically and emotionally stressed, this study has been largely discredited by a recently published consensus report endorsed by 110 child development
experts (Warshak, 2013), which found that McIntosh drew unwarranted conclusions from her unrepresentative and flawed data.