Stability in the integrated bilingual grammar: Tense exponency in North American Norwegian

Decades of research on bilingual grammars corroborate the integrated nature of these systems, leading to the conjecture that these representations are 'shared' (Marian & Spivey 2003, Kroll & Gollan 2014, Putnam et al. 2018). A specific population of bilinguals, namely heritage language speakers, shows a tendency for highly variable allomorphy (Polinsky 2018, Putnam et al. 2021); however, with this aspect of grammar that is often in a state of flux, there are instances of stability. Here we thoroughly investigate the stability of tense allomorphy of in North American Norwegian (NAmNo), a moribund heritage language spoken in the Upper Midwestern United States. Formally, we build upon initial observations provided by Lykke (2020), showing how a late-insertion approach to the syntax-phonological interface in combination with events, features, and precedence (EFP) phonology (Raimy 2000, Papillon 2020, Idsardi 2022) provides a straightforward account of the structural complexities that determine exponency in bilingual grammars.