BACKGROUND: Transitional objects provide security and symbolic connection with valued others when separated from them. Bereaved parents often keep, cherish and visit saved objects of their deceased child. This research examined the hypothesis that these objects behave as transitional objects of grief in bereaved mothers during three years following their infants' deaths from Sudden Infant Death Syndrome. METHODS: Questionnaires were administered asking about the presence of kept objects and momentos from their deceased infant, and the frequency, location and emotions experienced during visits to them. Diagnostic criteria for Prolonged Grief Disorder (PGD) were assessed using the Parental Bereavement Questionnaire. RESULTS: 98.6% of the mothers reported having transitional objects of grief, and most visited them more frequently than once per week regardless of PGD status. Mothers with PGD reported significantly more distress when visiting the objects, especially those visiting them privately. Mothers with PGD who felt comforted by the objects had lower risk for finding life meaningless or finding discussion about the infant intolerable. CONCLUSIONS: Transitional objects of grief are common and associated with key aspects of grief. There is a need to understand the potential therapeutic uses of transitional objects in promoting bereavement adjustment.