The acquisition of grammatical morphemes in autistic children: a critique and replication of the findings of Bartolucci, Pierce, and Streiner, 1980.

Hobson (1984) copied an earlier study that claimed autistic kids learn grammar in a weird order. The team tested the same morphemes—little word bits like “-ing” and plural “s.” They used the same tasks and scoring rules.

The goal was to see if the odd order held up when methods were tighter.

The accuracy pattern repeated: autistic kids scored like the first study. But the authors say the earlier claim of “deviant” grammar is shaky. The problem is how kids were picked and matched.

Meng et al. (2026) extends this idea. They tracked Mandarin-speaking autistic kids for two years. The children learned markers in the same order as typical peers—just slower. This supports P’s view: order is normal, speed is not.

Mazzaggio et al. (2020) looks at first like a clash. Italian autistic kids used pronouns less often and in odd ways. The difference is focus: P counted accuracy on fixed morphemes; Greta counted choice of pronoun versus verb ending. Both can be true: kids may master endings on time but still avoid pronouns for social reasons.

Charman (2004) backs P’s warning. The review lists pitfalls when we try to match preschoolers on language level. Using a single test score can hide real differences and create fake “deviance.”

Before you label an autistic child’s grammar as disordered, check your match group and task. Use several language measures, not just one. Then teach the next morpheme in the usual developmental order—slow pace is expected, not wrong order.