Does reading in shallow L1 orthography slow attrition of language-specific morphological structures?

This study looks at the relationship between L1 (Russian) attrition and L1 reading ability in Russian-English-speaking bilingual children. Ten Russian-English bilingual children and 10 adults participated in this study. Nine out of 10 children participants were born in the US and used L1 as their primary language of interaction within the family, but the intensity and the length of uninterrupted L1 exposure differed for each child.