This short report examines the association between smoking behaviours of mothers and their 15 year old children, and whether there is a difference between families headed by a mother living alone or with a partner. It is based on data collected from a cohort of young people and their mothers (N = 967), resident in the West of Scotland. We found no evidence that children of lone mothers smoke more because their mothers do; the familial transmission of smoking behaviour, at 15, appeared to be less apparent in households headed by lone than cohabiting mothers.