The aim of this project is to assess whether video materials from the BBC Tiny Happy People (THP) campaign are effective in terms of improving the language skills of socioeconomically disadvantaged children before they start school. This project will also look at how useable the service is for parents in terms of acceptability, effects on self-efficacy and implementation of advice.

The current study will evaluate BBC Education's Tiny Happy People initiative (https://www.bbc.co.uk/tiny-happy-people) which seeks to reduce the impact of social and economic disadvantage on children's language skills before they arrive at primary school. BBC Education have created videos for parents and other caregivers with information about child development, tips and activities as well as other content of interest. The aim of the evaluation is to find out how parents feel about the materials and whether the videos promote a) caregiver confidence at 12, 18 and 24 months, b) caregiver-infant interaction at 12, 18 and 24 months and c) child language at 18 and 24 months. The primary outcome is expressive vocabulary size at 17-18 months. Families with 4- to 9-month-old infants who would like to take part will be randomly allocated either to a language support group or a physical health active control group and sent short, age-appropriate advice videos by text message three times a month until their children are 18 months old (with follow up videos for children until the age of 2 years where possible given study time limits).

Inclusion Criteria:

Families must:

• be raising their child as a monolingual English speaker (at least 80% of the language they hear in the home is English)
• have a postcode in deciles 1-5 of the Office of National Statistics Index of Multiple Deprivation
• have access to the internet and a device to watch videos (via smart phone)

Infants must:

• be full term
• have a healthy birthweight

Exclusion Criteria:

Neither caregivers nor infants must have any significant known physical, mental or learning disability

Anonymised Individual Participant Data will be archived using the Open Science Framework's repository. For those participants who give permission, video data will also be archived such that researchers who have signed a confidentiality agreement can access this data.

Data will be made available at the same time as publication, anticipated within 2 years of study completion. It will remain available for at least 10 years.