Father and Sibling Involvement in Home Rehabilitation: Longitudinal Effects on Infant Development and Maternal Wellbeing in Bulawayo, Zimbabwe.

Families were not randomly assigned; they were grouped by what they were already doing at home, so any difference may come from other things about these families rather than from having more caregivers. The authors name sibling age, temperament and how much home practice took place as things they could not measure. Mothers' employment status differed between groups at the start (p = 0.003), so socioeconomic differences between the groups were not fully ruled out. No new intervention was introduced. Everyone was already on the same home programme and the study only watched what happened. Follow-up lasted three months, which the authors say is probably too short to detect change in language or motor development. The sample was weighted towards milder disability (about half to two-thirds of each group had mild impairment), so it may say little about children with more severe involvement. The 4.4-point cognitive difference left all three groups inside the Bayley 'average' range of 90 to 109, so it likely would not change how an individual child is classified. Mothers rated their own mental health and quality of life, so answers may reflect mood or what they thought the researchers wanted to hear, and the quality-of-life gains were small in absolute terms. Who took part at home was reported by caregivers and checked by clinic staff, so the amount of practice that actually happened is not known.

The authors declare no conflicts of interest, and the funding statement reports nothing to declare: no funder is named and no company involvement is described. They also state that Claude, a large language model, was used only for language editing and clarity, with no role in the design, data, analysis or interpretation, and that the authors take full responsibility for the content.

Do not read this as proof that involving fathers and siblings improves a child's development. Families were not randomly assigned and everyone was already on the same home programme, so the extra caregivers cannot be separated from other differences between these families. The only between-group difference that survived adjustment was 4.4 points on the cognitive scale, which stayed inside the average range, and the authors say an intervention study is needed to test it.