Herein, we contextualize, problematize, and offer some insights for moving beyond the problem of monolingual comparative normativity in (psycho) linguistic research on bilingualism. We argue that, in the vast majority of cases, juxtaposing (functional) monolinguals to bilinguals fails to offer what the comparison is supposedly intended to do: meet the standards of empirical control in line with the scientific method. Instead, the default nature of monolingual comparative normativity has historically contributed to inequalities in many facets of bilingualism research and continues to impede progress on multiple levels. Beyond framing our views on the matter, we offer some epistemological considerations and methodological alternatives to this standard practice that improve empirical rigor while fostering increased diversity, inclusivity, and equity in our field.

Across languages, structures with non-canonical word order have been shown to be problematic for both child and adult heritage speakers. To investigate the linguistic and child-level factors that modulate heritage speakers’ difficulties with non-canonical word orders, we examined the comprehension and production of three Mandarin non-canonical structures in 5- to 9-year-old Mandarin-English heritage children and compared them to age-matched Mandarin-speaking monolingual children and adults. Specifically, we examined how linguistic properties, such as linear word order, presence or absence of morphosyntactic cues, and surface structural overlap between languages, as well as child-level factors, such as chronological age and current home language use affect the acquisition of non-canonical structures in heritage children and their monolingual peers. Results showed that although heritage children could use morphosyntactic cues, they did not show monolingual-level sensitivity to passive-related morphology. Additionally, children produced more canonical SVO word order, which is shared between English and Mandarin, and preferred the reverse interpretations of non-canonical structures in comprehension. These responses were taken as evidence for cross-linguistic influence from the majority to the minority language. Finally, although non-canonical structures caused difficulties for child heritage speakers, their performance was modulated by structure and improved with age, over and above heritage language use.