Background Accelerating reduction in infant and other child mortality rates calls for comprehensive child survival strategies. Early recognition of illness and timely seeking of treatment are critical elements to prevent child deaths, and cultural explanation for these care-seeking behaviours is important. The present article reports (i) mothers' recognition of illness and (ii) triggers of treatment related to some childhood illnesses among a migrant tribal community living in Bhubaneswar city, India. Methods From the four tribal dominated slums, 175 Santal tribal households were selected based on the criteria, viz. (i) the family should have migrated within the past 12 years and (ii) having a child aged 0-14 years. Semi-structured interviews were conducted with mothers for data related to illnesses occurred to their youngest child during past 1 year. Results The recognition of illness was made based on multiple symptoms. Triggers of treatment and care-seeking behaviour vary from illness to illness. Usually people wait for 2-3 days after onset of any illness, expecting the symptoms to subside automatically. Late onset symptoms and severity trigger mother to take child for treatment. Conclusion Mothers were able to recognize the childhood illnesses. There was substantial delay in seeking care. Hence, provision of primary health care and health education-based interventions are needed to improve the mothers' recognition and care-seeking behaviour.