The monolingual girl was recorded once a month. While, the bilingual boy MAN was recorded twice a month, one recording per language. For the bilingual child, the recordings were conducted as monolingual as possible, so either it only included the German-speaking mother or only the Italian-speaking father. One important thing noted in this study, is MAN spent two- three weeks in Austria with his grandparents. In the end, it was found that MAN had acquired twice as many words than the monolingual girl. However, there was not a striking difference regarding word categories in comparisons of the bilingual boy’s lexicon verse the monolingual child. They found a striking increase in that the rate of acquisition after they reached the size of about 50 words, this increase in vocabulary is known as a vocabulary