Families including a young child with a significant cognitive and motor developmental delay need to adapt their routines to the child's needs, while balancing the resources, needs and values of the whole family system. We aim to characterize if and how their routines are sustainable in terms of ecological fit, congruence and meaningfulness, in comparison with families including a typically developing child. Based on an adapted version of the Ecocultural Family Interview, conducted with one or both parent(s), the routines of 6 families within the study group and 5 families within the control group were analysed by combining directed content analysis with quantitative ratings. A myriad of common as well as group-specific indicators of ecological fit, strategies for reaching congruence as well as reported family values were identified. Parents actively influence family life sustainability. However, families including a child with complex needs are more dependent on others and could benefit greatly from improving the organization of formal support.