  Mothers of infants have specific demands in fostering emotional bonds with
their children, characterized by dynamics that are different from adult-adult
interactions, notably requiring heightened maternal emotional regulation. In
this study, we analyzed maternal emotional state by modeling maternal emotion
regulation reflected in smiles. The dataset comprises N=94 videos of
approximately 3 plus or minus 1-minutes, capturing free play interactions
between 6 and 12-month-old infants and their mothers. Corresponding demographic
details of self-reported maternal mental health provide variables for
determining mothers' relations to emotions measured during free play. In this
work, we employ diverse methodological approaches to explore the temporal
evolution of maternal smiles. Our findings reveal a correlation between the
temporal dynamics of mothers' smiles and their emotional state. Furthermore, we
identify specific smile features that correlate with maternal emotional state,
thereby enabling informed inferences with existing literature on general smile
analysis. This study offers insights into emotional labor, defined as the
management of one's own emotions for the benefit of others, and emotion
regulation entailed in mother-infant interactions.
