The Small Step intervention program has three alternating treatment foci (B, C, and D) divided into five different steps, each lasting for 6 weeks (in total 30 weeks). The three treatment foci are Communication, Hand function and Mobility/gross motor function. The Hand function and Mobility steps will be conducted during two time-periods and the order will be randomised. Communication will have one intervention period during step III. The training will be conducted in the children's home by the parents on a daily basis under weekly supervision by the therapist responsible for each specific step of the intervention. General principles for the small step program are: a) collaborative goal-setting; b) promote infant's self-initiated actions; c) use of enriched home environment, d) intensity and repetition.