This study aims to establish a standardized, synchronized data collection system for pediatric symptom questionnaires, cough sounds, and breath sounds, and to construct a multimodal database of pediatric respiratory diseases including both disease cases and healthy controls. Using the final research labels determined by clinicians' diagnoses, health status assessments, and research team review as the reference standard, this study will develop and validate a multimodal assisted diagnostic model for common pediatric respiratory diseases based on symptom questionnaires, cough sounds, and breath sounds. The study will primarily evaluate the diagnostic performance of the model in distinguishing healthy children from children with respiratory diseases, screening for asthma and asthma-related cough, and identifying pneumonia, tracheitis/bronchitis, upper airway-related diseases, and common causes of chronic cough. It will also assess the incremental value of cough sounds and breath sounds beyond symptom questionnaire information.