Society can promote children's mental health at an early stage by creating good conditions with, for example, general parental support programs that are offered to all parents. One program that has been developed is called All Children in Focus (ACF) [in Swedish: Alla Barn i Centrum (ABC)] which has been evaluated for parents with children aged 3-12 years. The results showed effects on parenting ability, parenting strategies and on children's well-being. Staff in child health care (CHC), a natural arena for parental support programs reaching almost all families, have requested modifications in the program ACF to involve parents with younger children. The parent groups offered within CHC today are not evaluated in younger children and could be thus replaced by researched parental support based on evidence.

The investigators therefore want to study the effects of a modified version of ACF for parents of children 1-2 years (Little ACF) to see if Little ACF can strengthen parenting ability and have effects on children's social and emotional development. Parents within CHC are asked to participate and are randomly assigned to Little ACF or the regular CHC program plus a lecture. Little ACF is offered during four group meetings and potential effects are measured with questionnaires. Measurements are made before randomisation, during and after participation in Little ACF. Children's behavior is followed up at 3 years through questionnaires and CHC documentation.

The study can provide important knowledge about how Little ACF can promote children's mental health and strengthen parents. The investigators see it as a strength that Little ACF is based on research and on dialogue with parents and professionals. Little ACF, which is aimed at everyone, can form a basis for identifying families and children who need preventive and treatment measures.

Promotion of mental health is an important topic and early interventions may be the most cost-effective investment for the society. The Child Health Care (CHC) in Sweden reaches 99% of parents with infants and is the society's major promotive support during the first years of life. All Children in Focus (ACF) [in Swedish: Alla Barn i Centrum (ABC)] is a universal program aiming to support positive parental strategies and promote child well-being. ACF has shown positive effects for parental efficacy and strategies and for child well-being at age 3-12 years. In this 3-year project the investigators aim to gain knowledge about how ACF given to parents with children 1-2 years (Little ACF) may influence parenting and child well-being. Specific research questions are how Little ACF in comparison to care as usual (CAU) within CHC can:

• strengthen strategies of emotional regulation in parents,
• promote parenting practices,
• promote child well-being
• lead to reduction of child behavior problems (externalizing/internalizing),
• engage and retain parents in groups?

Parents with infants of 12-24 months that are registered at any of the included CHC centers in Stockholm, Gotland and mid-Sweden will be asked for participation. Recruitment will be performed at the ordinary 10-, 12- or 18-months visits of the child. The CHC nurse will ask parent/s for participation verbally and parents will be provided the information and consent form and a pamphlet about the study. Parents who are interested in participating will be sent a link via email with the same information and consent form that can be signed digitally. Thereafter they will be sent the questionnaire. When the CHC nurse has recruited twice as many parents as a full Little ACF group, the researchers will randomize the parents into the two groups, one receiving the intervention Little ACF and the other a control group receiving CAU and digital lectures. The CHC nurse will notify the parents about which group they have been randomized to and a description on how the study will proceed.

A previous randomized study of ACF (aimed at parents with children 3-12 years) showed an effect size (Cohen's d) of 0.30 for parental self-efficacy. Since this study compares Little ACF with CAU including lectures (instead of waiting list), a marginally smaller effect (d = 0.25) between the groups is expected. With a significance level of 95% (p-value 0.05) and a power of 80%, it would thus be needed 251 participants in each group. A drop-out rate of 25% is expected, which means that a total of 670 families would need to be included.

Each Little ACF group will consist of parents of 5-7 children, which means that about 60-70 groups will be needed and thus a total of 25 group leader pairs if each pair leads three groups. The pair of group leaders consist of one CHC nurse and one social worker or other profession with experience of working with parents of young children. Group leaders will be provided a training containing theory, practical exercises, and supervision. The training is spread out over three occasions taking place every other week to allow for the possibility to start Little ACF groups in between the training sessions. After the training, the group leaders will be offered monthly group supervision.

Effects of Little ACF on positive parenting and strategies are assessed through parental questionnaires distributed digitally to be completed independently by the parents. Child well-being is measured through parental questionnaires and data in CHC records. CHC nurses will be invited to semi-structured interviews to gain a better knowledge in how the experience of Little ACF affect daily work at CHC. Quantitative data will be analyzed statistically with linear regression models and qualitative data will be analyzed using thematic analysis.

This study adds to the evidence of promotion during infancy and give information if Little ACF is effective for parents and young children. It may also reduce needs of future interventions of mental health problems.

Inclusion Criteria:

• Parents of children in the age of 1-2 years that are registered at the CHCs included in the study

Exclusion Criteria:

• Parents in need of interpreter will be excluded