The present study examined the processes through which recurrent episodes of otitis media influence children's attachment security. The model guiding the research suggests that mothers of children who experience recurrent episodes of otitis media have higher levels of parenting stress, which can have a direct negative effect on attachment security. As well, an increase in parenting stress may be indirectly related to attachment security by decreasing maternal sensitivity, a known precursor of attachment security. A structured telephone illness interview was conducted with mothers of 161 children every 2 weeks for 6 months to determine the number of episodes of otitis media children experienced. At the end of this period, parenting stress, attachment security, and maternal sensitivity were assessed. Recurrent episodes of otitis media did negatively affect attachment security by increasing mothers' perceptions of their children as behaving more negatively. Parenting stress was not related to maternal sensitivity; however, maternal sensitivity did predict attachment security.