This paper reports a case study of one little boy we call “Tim,” who learned language slowly and with difficulty. The study was based on eight one-hour video-recorded play sessions with Tim and his mother, starting when he was 2 years, 9 months old until he was about 5 years old. Because we were studying the language development of a child with a language disorder who could be expected to be a child with a learning disability in his school years, the study was prospective. Our study was also retrospective because we saw Tim again when he was 8 years old and in his third year in a classroom for children with special educational needs because of learning disabilities. Using the earlier recorded observations of Tim's developing language behaviors, we could go back and observe how he learned language, how his language learning varied from normal language development, and something about how difficult language learning is. The study emphasizes the importance of observing and describing the behaviors of individuals rather than groups for identifying both the regularities as well as the variation in language behavior and, more important, for understanding a language disorder as both a learning disability and a variant of language development.