Research on passive sentence acquisition has found these non-canonical structures to be particularly challenging in both typical and atypical language development due to their syntactic complexity. My research project investigates how monolingual Italian-speaking children with syntactic Developmental Language Disorder (SyDLD) and those with Autism Spectrum Disorder and Language Impairment (ASD-LI) comprehend and produce different types of Italian passive constructions. The study seeks to determine whether the two clinical groups behave similarly — possibly pointing to overlapping syntactic difficulties — or whether their error patterns diverge, strongly suggesting different underlying mechanisms.