How adults talk to children and whether it influences their language development
The topic for the research paper is the role adults play in the acquisition of language in young children, more specifically, how adults talk to young children.
The topic on how adults talk to children and whether it influences
their language development is usually referred to as Caretaker talkor Mothereseand it is related to Foreigner talk(how native speakers talk to people with foreign accents), so incorporating that topic would also be relevant. A book by Snow, CE & Ferguson, C. (Eds.). (1977), Talking to children: Language input and acquisition, has some excellent articles in it directly related to this topic. I would also recommend searching the index of the Journal of Child Language, and The Language Instict by Stephen Pinker.