The way that Scott Lilienfeld used his word choice to describe bilingualism such as "experience delay," "syntax is more affected," and "popular claims that children are slowed down in cognitive development" seemed like he was hinting that being bilingual will harm a child rather than help him or her at a young age. Yet, one of my friends was taught Russian by her parents and taught English outside of her house; thus, she didn't have any hindrance or delay but instead was more active and developed in language than her monolingual peers. Furthermore, Scott Lilienfeld explains that the dominate language is usually the first language that the child heard most often. Personally, I never heard the English language until I was seven years old; yet, English is my dominate language. I believe that language is not something that can have a direct explanation, because there are always other rival hypotheses that play a role in the development.
To continue, I'm a twin and I've learned my second language at age seven; yet, my language capability was never worse than the language of my peers who were neither a twin nor bilingual. Also, Scott Lilienfeld states that twins develop a secret language to simply attempt to use their native language, but don't all kids develop their language? Is a secret language considered as a twin pointing at an object that they want for the other twin to get it for them? All kids interact with each other with their own language; thus, twins should not be characterized as the only once that possess their own language. This makes me wonder how research on twins and language was completed. Is the research on twins as accurate as Scott Lilienfeld directs it to be?