duration of this CP. L2 attrition In Hansen & Reetz-Kurashige (1999), Hansen cites her own research on L2-Hindi and Urdu attrition in young children. As young pre-school children in India and Pakistan, the subjects of her study were often judged to be native speakers of Hindi or Urdu; their mother was far less proficient. On return visits to their home country, the United States, both children appeared to lose all their L2 while the mother noticed no decline in her own L2 abilities. Twenty years later, those same young children as adults comprehend not a word from recordings of their own animated conversations in Hindi-Urdu; the mother still understands much of them. Yamamoto (2001) found a link between age and bilinguality. In fact, a number of factors are at play in bilingual families. In her study, bicultural families that maintained only one language, the minority language, in the household, were able to raise bilingual, bicultural children without fail. Families that adopted the one parent – one language policy were able to raise bilingual children at first but when the children joined the dominant language school system, there was a 50% chance that children would lose their minority language abilities. In families that had more than one child, the older child was most likely to retain two languages, if it was at all possible. Younger siblings in families with more than two other brothers and sisters had little chance of maintaining or ever becoming bilingual. Age of arrival There are few principled and systematic investigations of FLA specifically investigating the impact of AoA. However, converging evidence suggests an age effect on FLA which is much stronger and more clearly delineated than the effects that have been found in SLA research. Two studies that consider prepuberty and postpuberty migrants (Ammerlaan, 1996, AoA 0–29 yrs; Pelc, 2001, AoA 8–32 years) find that AoA is one of the most important predictors of ultimate proficiency, and a number of studies that investigate the impact of age among postpuberty migrants fail to find any effect at all (Köpke, 1999, AoA 14–36 yrs; Schmid, 2002, AoA 12–29 yrs; Schmid, 2007, AoA 17–51 yrs). A range of studies conducted by Montrul on Spanish heritage speakers in the US as well as Spanish-English bilinguals with varying levels of AoA also suggests that the L1 system of early bilinguals may be similar to that of L2 speakers, while later learners