Heritage language (HL) speakers tend to assess their linguistic competence in binary terms, such as “good” and “bad,” and to consider that they speak “slang” or a “broken” language (Byram et al., 2021). However, research on HL production does not confirm these perceptions: Rinke et al. (2024) show that structures that prove most challenging for HL bilinguals are also problematic for monolingual speakers. Furthermore, Torregrossa et al. (2023) indicate that age and formal instruction in the HL may lead to better performance in those challenging structures. Drawing on examples from Portuguese grammar, this talk discusses research on linguistic production in ...