Children born with a cleft lip and palate (CLP) are known to be at risk for speech-language disorders that impact academic and social emotional growth. Even at very young ages (\<3 years), speech-language disorders are already observed. It is hypothesized that speech-language intervention delivered before the age of 3 years old could decrease the impact of CLP on speech-language development. This would result in a decreased need for speech-language therapy on the long-term and a reduced burden of care on children, families and health services. However, no evidence is yet available to support any specific model of early speech-language intervention in this population. Consequently, no standardized clinical practice guidelines are available yet. Symbolic gesture training in combination with verbal input expands the natural communication of young children including multimodal speech-language input (i.e., verbal and manual input) via caregivers who act as co-therapists. To contribute to the evidence-based practice in the field of cleft speech therapy, this research project aims to determine the effectiveness and feasibility of symbolic gesture training in one-year old children with CLP by comparing different intervention approaches based on perceptual, psychosocial and qualitative outcome measures.