This article provides an overview of the research on morpho-syntactic challenges in Swedish-speaking children with developmental language disorder (DLD), compared with typically developing (TD) children learning Swedish as their first and second language (L1/L2). Children with DLD show vulnerabilities with verb finiteness, the possessive construction, and noun phrase gender agreement, as well as word-order in nonsubject initiated sentences. For L2-learners, word order and the noun phrase gender agreement present main challenges. We discuss to what extent these morpho-syntactic weaknesses can be explained by different theoretical accounts and identify future research needs. Surface similarities between groups may originate from different factors and more knowledge is needed to inform educational and clinical practice for both of these groups of children.