This is a longitudinal and naturalistic study of the bilingual acquisition of English and Turkish languages simultaneously by a 28-month old Turkish infant. The emphasis is on empirical findings collected from a two-year period of observations beginning from the subject's birth and lasting until his 28-month old linguistic status. The study is based on careful distributional analyses of the performed data and the findings contrasted and compared as per two languages. The results revealed that two languages are acquired as a single linguistic system at least until the age of 28 month-old, perhaps due to the fact that syntactical operations have not started yet. In addition, the findings prove that the extent to which acquisitional differences between the two languages which bilinguals receive depends on factors such as variation in the amount of input and the quality rather than the quantity of time spent with the exemplar. The data obtained in this longitudinal observational study are expected to contribute not only to the bilingual and multilingual linguistic studies but first language acquisition studies as well in that the study is important in terms of its scope.