Background: This study examines family caregivers' knowledge of the social and behavioral changes autistic children face during puberty, focusing on challenges and support gaps at the Sudanese Egyptian Center in Alharam, Giza Governorate, Cairo Egypt. Aim: The study aims to assess family caregivers' knowledge of behavioral and social changes in autistic children during puberty, assess the family caregivers’ attitude towards these changes, and assess their satisfaction with services provided affects their support. Methods: A mixed research design was used, combining both quantitative and qualitative approaches. The data were collected using questionnaires, which included both Likert-scale questions and an open-ended question to capture family Caregivers' opinions. The sample consisted of 40 family Caregivers from the Sudanese Egyptian Center, selected through purposive sampling. The quantitative data were analyzed using descriptive statistics (mean scores, frequencies, and percentages) to assess family Caregivers' awareness, confidence, and perceptions. For the open-ended responses, content analysis was applied to identify common themes, which were then coded and quantified to integrate them with the quantitative findings. To examine potential relationships between family Caregivers' demographics and their awareness, inferential analysis was carried out using the chi-square test, with a significance level set at p < 0.05. Results: The results showed that family Caregivers had limited knowledge, especially of behavioral changes during puberty, and low confidence in handling both changes. Misconceptions were common, and a significant link was found between family Caregivers' gender and awareness of behavioral changes (p = 0.023). Conclusion: This study emphasizes the importance of increasing family Caregivers' knowledge and training to better support their children through puberty, ultimately improving their developmental outcomes during this crucial phase.